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Filed Pursuant to Rule 424(b)(5)
Registration No. 333-271336

PROSPECTUS SUPPLEMENT |  | (To the Prospectus dated April 19, 2023)

4,285,715 Shares

Common Stock

We are offering 4,285,715 shares of our common stock. Our common stock is listed for trading on the Nasdaq Global Select Market under the symbol “ATEC.” On April 18, 2023, the last reported sale price of our common stock was $15.69 per share.

Our business and investment in our common stock involve significant risks. These risks are described under the caption “Risk Factors ” beginning on page S-6 of this prospectus supplement, as well as the risk factors contained in the documents incorporated by reference into this prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

|  | Per Share |  |  | Total |
Offering price |  | $ | 14.00 |  |  | $ | 60,000,010 |
Underwriting discounts and commissions(1) |  | $ | 0.49 |  |  | $ | 2,100,000 |
Proceeds, before expenses, to us |  | $ | 13.51 |  |  | $ | 57,900,010 |

(1) | See “Underwriting” for a description of all compensation payable to the underwriter.

The underwriter expects to deliver the shares against payment in New York, New York on or about April 21, 2023.

Sole Book-Running Manager

TD Cowen

Prospectus Supplement dated April 19, 2023.

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TABLE OF CONTENTS

Prospectus Supplement

PROSPECTUS SUPPLEMENT SUMMARY |  |  | S-1 |
RISK FACTORS |  |  | S-6 |
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS |  |  | S-9 |
USE OF PROCEEDS |  |  | S-11 |
DIVIDEND POLICY |  |  | S-12 |
DILUTION |  |  | S-13 |
CERTAIN MATERIAL U.S. FEDERAL INCOME AND ESTATE TAX CONSIDERATIONS FOR NON-U.S. HOLDERS OF OUR COMMON STOCK |  |  | S-15 |
UNDERWRITING |  |  | S-20 |
LEGAL MATTERS |  |  | S-27 |
EXPERTS |  |  | S-27 |
WHERE YOU CAN FIND ADDITIONAL INFORMATION |  |  | S-27 |
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE |  |  | S-28 |

Prospectus

ABOUT THIS PROSPECTUS |  |  | 1 |
WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE |  |  | 2 |
ABOUT ALPHATEC |  |  | 4 |
RISK FACTORS |  |  | 5 |
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS |  |  | 6 |
USE OF PROCEEDS |  |  | 7 |
DESCRIPTION OF CAPITAL STOCK |  |  | 8 |
DESCRIPTION OF DEBT SECURITIES |  |  | 13 |
DESCRIPTION OF WARRANTS |  |  | 21 |
DESCRIPTION OF UNITS |  |  | 23 |
GLOBAL SECURITIES |  |  | 24 |
PLAN OF DISTRIBUTION |  |  | 27 |
LEGAL MATTERS |  |  | 29 |
EXPERTS |  |  | 29 |

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document is in two parts. The first part is the prospectus supplement, including the documents incorporated by reference herein, which describes the specific terms of this offering. The second part, the accompanying prospectus, including the documents incorporated by reference, provides more general information. Generally, when we refer to this prospectus, we are referring to both parts of this document combined. Before you invest, you should carefully read this prospectus supplement, the accompanying prospectus, all information incorporated by reference herein and therein, as well as the additional information described under “Where You Can Find Additional Information” on page S-26 of this prospectus supplement. These documents contain information you should consider when making your investment decision. This prospectus supplement may add, update or change information contained in the accompanying prospectus. To the extent that any statement that we make in this prospectus supplement is inconsistent with statements made in the accompanying prospectus or any documents incorporated by reference therein, the statements made in this prospectus supplement will be deemed to modify or supersede those made in the accompanying prospectus and such documents incorporated by reference therein.

You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and in any free writing prospectuses we may provide to you in connection with this offering. We have not, and the underwriter has not, authorized any other person to provide you with any information that is different than that contained or incorporated by reference in this prospectus supplement, the accompanying prospectus and any related free writing prospectus that we provide you in connection with the offering. If anyone provides you with different or inconsistent information, you should not rely on it. We are offering to sell, and seeking offers to buy, shares of our common stock only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus supplement must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus supplement outside the United States. This prospectus supplement does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

When we refer to “Alphatec,” “we,” “our,” “us” and the “Company” in this prospectus, we mean Alphatec Holdings, Inc. and its consolidated subsidiaries, unless otherwise specified. “Alphatec Spine” refers to our wholly owned operating subsidiary Alphatec Spine, Inc. “SafeOp” refers to our wholly owned operating subsidiary SafeOp Surgical, Inc. “EOS” refers to our wholly owned operating subsidiary EOS imaging S.A. When we refer to “you,” we mean the potential holders of the applicable series of securities.

Industry and Market Data

The market data and certain other statistical information used throughout this prospectus supplement and the accompanying prospectus are based on independent industry publications, government publications and other published sources. Some data, such as our estimates of the potential pool of donors and our potential addressable commercial opportunity, are also based on our good faith estimates. Although we believe these third-party sources are reliable as of their respective dates, neither we nor the underwriter has independently verified the accuracy or completeness of this information. The industry in which we operate is subject to a high degree of uncertainty and risk due to a variety of factors, including those described in the sections entitled “Risk Factors” in this prospectus supplement and in the documents incorporated by reference to this prospectus supplement. These and other factors could cause results to differ materially from those expressed in these publications.

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Trademarks and Tradenames

The Alphatec name and logo and the names of products and services offered by Alphatec, Alphatec Spine, SafeOp and EOS are trademarks, registered trademarks, service marks or registered service marks of Alphatec. All other trademarks, trade names and service marks appearing in this prospectus or the documents incorporated by reference herein are the property of their respective owners. Use or display by us of other parties’ trademarks, trade dress or products is not intended to and does not imply a relationship with, or endorsements or sponsorship of, us by the trademark or trade dress owner. Solely for convenience, trademarks and tradenames referred to in this prospectus appear without the ® and ™ symbols, but those references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or that the applicable owner will not assert its rights, to these trademarks and tradenames.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights selected information about us, this offering and information appearing elsewhere in this prospectus supplement, in the accompanying prospectus and in the documents incorporated by reference herein and therein. This summary is not complete and does not contain all the information you should consider before investing in our common stock pursuant to this prospectus supplement and the accompanying prospectus. Before making an investment decision, to fully understand this offering and its consequences to you, you should carefully read this entire prospectus supplement and the accompanying prospectus, including “Risk Factors” beginning on page S-6 of this prospectus supplement, the financial statements, and related notes, and the other information that we incorporated by reference herein, including our Annual Report on Form 10-K for the year ended December 31, 2022 and our other filings with the SEC that we file from time to time. Unless otherwise indicated or the context otherwise requires, all references in this prospectus supplement to “Alphatec,” the “Company,” “we,” “us,” and “our” mean Alphatec Holdings, Inc. and its consolidated subsidiaries.

Alphatec Holdings, Inc.

We are a medical technology company focused on the design, development, and advancement of technology for better surgical treatment of spinal disorders. Through our wholly owned subsidiaries, Alphatec Spine, SafeOp and EOS, our mission is to revolutionize the approach to spine surgery through clinical distinction. We are focused on developing new approaches that integrate seamlessly with our expanding Alpha InformatiX™ product platform to better inform surgery and to achieve the goal of spine surgery more predictably and reproducibly. We have a broad product portfolio designed to address the spine’s various pathologies. Our ultimate vision is to be the standard bearer in spine.

In 2018, we embarked on a business transformation that has replaced 100% of the executive team, 94% of our Board of Directors, and over 90% of the remaining team with experienced professionals. Efforts that year founded our Organic Innovation Machine™, our in-house product design, development and testing capabilities aimed at the creation of clinical distinction, and furthered the strategic transition of our sales force to a more dedicated, clinically astute team.

From 2019 through 2021, our focus was on building a foundation capable of supporting the organization as we scale into a larger business. We developed and released several key elements of our approach-based portfolio, including a comprehensive posterior fixation system and approach-specific IdentiTi implants. We also acquired and integrated SafeOp, technology that integrates with our approaches to provide information about both the location and the health of nerves intra-operatively. SafeOp became the informational backbone of the Prone TransPsoas (“PTP”) approach, which we developed and launched in 2020 to advance lateral spine surgery. We invested in new headquarters to substantially increase surgeon and sales training capacity and opened a distribution facility in Memphis, TN to ensure predictable and expedient surgical support as we grow. We also acquired EOS imaging to expand on the informational competitive advantage established with SafeOp. EOS systems enable full-body, calibrated, 3D images that integrate throughout the arch of patient spine care to influence procedure planning and improve and objectify the understanding of global alignment. As we execute against our vision for EOS technology, we believe it will set new standards for spine care.

Our ability to leverage our collective spine experience, coupled with a willingness to invest in every component of the advanced spine approaches that we bring to market has fueled market-leading growth in every year since early 2018.

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Recent Developments

Asset Transaction

On April 19, 2023, Alphatec Spine, Integrity Implants Inc., a Delaware corporation (“Integrity”), Fusion Robotics, LLC, a Delaware limited liability company (“Fusion” and together with Integrity, collectively, the “Sellers”) and wholly owned subsidiary of Integrity, and stockholders of Integrity identified on Schedule A of the Purchase Agreement (as defined below) (the “Key Stockholders”) entered into an Asset Purchase Agreement (the “Purchase Agreement”).

Upon the terms and subject to the conditions of the Purchase Agreement, the Sellers agreed to sell to Alphatec Spine all of the Sellers’ right, title and interest in, to and under all of the assets, properties and rights, except for the specific excluded assets, that relate to, or are used or held for use in connection with, Sellers’ REMI Robotic Navigation System business (the “REMI Business” and such asset acquisition, the “Asset Transaction”). Alphatec Spine also agreed to offer employment to certain of Sellers’ employees of the REMI Business upon consummation of the Asset Transaction. As consideration for the purchase of the assets in the Asset Transaction, Alphatec Spine agreed to pay to the Sellers cash consideration of $55,000,000. The Asset Transaction was also consummated on April 19, 2023.

The Purchase Agreement contains customary representations and warranties and of Alphatec Spine and of the Sellers relating to the REMI Business and the assets acquired in the Asset Transaction. Additionally, the Purchase Agreement provides for customary covenants of the Sellers and Alphatec Spine, as well as indemnification provisions subject to specified limitations. In addition, for a period of three years after the closing of the Asset Transaction, the Sellers have agreed not to compete or engage in any business competing with the REMI Business.

Financial Update

Our preliminary total revenue for the first quarter ended March 31, 2023 grew over 52% year-over-year to an expected range of between $108.0 million and $109.5 million. Preliminary surgical revenue grew for the first quarter ended March 31, 2023 over 53% to an expected range of between $93.2 million and $94.3 million, led by surgical volume growth of at least 39% compared to the prior year period. Preliminary EOS revenue grew for the first quarter ended March 31, 2023 to an expected range of between $14.8 million and $15.2 million. The select, preliminary financial results are based on our current expectations and may be adjusted as a result of, among other things, completion of customary quarter-end close review procedures and further financial review.

Our cash and cash equivalents were approximately $117 million as of March 31, 2023 compared to approximately $85 million as of December 31, 2022, an increase of approximately $31 million. During the quarter ended March 31, 2023, we received $95.3 million in net proceeds from the Braidwell Term Loan, net of debt discount, debt issuance costs and other fees. In addition, we paid down the existing Midcap Revolving Credit Facility by $27.5 million during the quarter. Our cash balance increased by a net of $67.8 million in the quarter due to the aforementioned activity with the two financing facilities. The remainder of the offsetting decrease in cash of approximately $36 million in the quarter was primarily related to operating activities and investments in property and equipment. We have undrawn and available borrowings under the Midcap Revolving Credit Facility and the Braidwell Term Loan.

This financial data as of and for the three months ended March 31, 2023 is preliminary and may change, and is unaudited and based on information available to management as of the date of this prospectus supplement and is subject to completion by management of our financial statements as of and for the quarter ended March 31, 2023. We have provided ranges for preliminary revenues

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described above primarily because our financial closing procedures for the quarter ended March 31, 2023 are not yet complete. There can be no assurance that our final revenues for this period or cash position as of March 31, 2023 will not differ from these estimates, including as a result of quarter-end closing and review procedures or review adjustments and any such changes could be material. The preliminary results of operations for the quarter ended March 31, 2023 are not necessarily indicative of the results to be achieved for any future period.

Our independent registered public accountants have not audited, reviewed or performed any procedures with respect to such preliminary financial data and accordingly do not express an opinion or any other form of assurance with respect thereto. These results could change as a result of further review. Complete quarterly results will be announced during our first quarter financial results conference call and included in our Quarterly Report on Form 10-Q for the three months ended March 31, 2023.

Corporate Information

Alphatec Holdings, Inc. is a Delaware corporation incorporated in March 2005. Our principal executive office is located at 1950 Camino Vida Roble, Carlsbad, California 92008, and our telephone number is (760) 431-9286. We maintain an Internet website at www.atecspine.com. We have not incorporated the information on our website by reference into this prospectus supplement, and you should not consider it to be a part of this prospectus supplement.

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THE OFFERING

Common stock offered by us | 4,285,715 of shares of our common stock

Common stock to be outstanding after this offering | 110,925,362 shares of our common stock

Use of Proceeds | We intend to use the net proceeds of this offering for general corporate purposes, which may include working capital, capital expenditures, acquisitions, or research and development, as well as costs related to the purchase and post-closing integration with Alphatec of the REMI Business and research and development activities related to the integrated business. See “Use of Proceeds” on page S-12.

Risk Factors | See “Risk Factors” beginning on page S-6 of this prospectus supplement as well as the risk factors contained in the documents incorporated by reference to this prospectus supplement for a discussion of factors that you should read and consider before investing in our securities.

Nasdaq Global Select Market symbol | “ATEC”

T+1 Settlement | It is expected that delivery of the shares of common stock will be made against payment therefor on or about April 21, 2023, which is the first business day following the date hereof (such settlement cycle being referred to as “T+1”) and that investors in this offering will agree expressly to T+1 settlement as required by Rule 15c6-1 under the Securities Exchange Act of 1934, as amended.

The number of shares of our common stock to be outstanding following this offering is based on 106,639,647 shares of our common stock outstanding as of December 31, 2022. This number of shares excludes the following:

| ∎ |  | 2,915,827 shares of common stock issuable upon exercise of options outstanding as of December 31, 2022, at a weighted average exercise price of $3.38 per share;

| ∎ |  | 15,490,610 shares of common stock issuable upon exercise of warrants outstanding as of December 31, 2022, at a weighted average exercise price of $3.32 share;

| ∎ |  | 8,533,273 shares of common stock issuable upon the vesting of restricted stock units outstanding as of December 31, 2022;

| ∎ |  | 17,245,619 shares of common stock issuable upon conversion of convertible notes outstanding as of December 31, 2022; and

| ∎ |  | 9,561,253 shares of common stock reserved for future issuance under stock-based compensation plans as of December 31, 2022, including 118,514 shares of common stock reserved for issuance under our Amended and Restated 2007 Employee Stock Purchase Plan,

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| 1,268,514 shares of common stock reserved for issuance under our Amended and Restated 2016 Employee Inducement Award Plan, 7,619,000 shares of common stock reserved for future issuance under our 2017 Development Services Plan, 281,000 shares of common stock reserved for future issuance under our 2017 Distributor Inducement Plan, and 274,225 shares of common stock reserved for future issuance under our 2019 Management Objective Incentive Plan.

Except as otherwise indicated, all information in this prospectus supplement assumes:

| ∎ |  | no exercise of the outstanding stock options or warrants described above;

| ∎ |  | no vesting of outstanding restricted stock units described above; and

| ∎ |  | no conversion of outstanding convertible debt described above.

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RISK FACTORS

You should carefully consider the risks and uncertainties described in this prospectus supplement and the accompanying prospectus, including the risk factors set forth below and in the documents and reports filed with the SEC that are incorporated by reference herein, such as the risk factors under the heading “Risk Factors” in our annual report on Form 10-K for the year ended December 31, 2022 on file with the SEC, before deciding whether to invest in our common stock. The risks and uncertainties described below and those described in the filings incorporated by reference are not the only ones we face. If any of the following risks actually occurs, our business, financial condition or results of operations could be adversely affected. In such case, the trading price of our common stock could decline and you could lose all or part of your investment. Our actual results could differ materially from those anticipated in the forward-looking statements made throughout this prospectus supplement and in the documents incorporated by reference herein as a result of different factors, including the risks we face described below and those described in the filings incorporated by reference.

Risks Relating to the Asset Transaction

We may fail to realize the anticipated benefits of the Asset Transaction.

The success of the Asset Transaction will depend on, among other things, our ability to incorporate the REMI Business into our business in a manner that enhances our value proposition to clients and facilitates other growth opportunities. We must successfully include the REMI Business within our business in a manner that permits these growth opportunities to be realized. In addition, we must achieve the growth opportunities without adversely affecting current revenues and investments in other future growth. If we are not able to successfully achieve these objectives, the anticipated benefits of the Asset Transaction may not be realized fully, if at all, or may take longer to realize than expected. Additionally, management may face challenges in incorporating certain elements and functions of the REMI Business with the Alphatec business, and this process may result in additional and unforeseen expenses. The Asset Transaction may also disrupt the REMI Business’ and Alphatec’s ongoing business or cause inconsistencies in standards, controls, procedures and policies that adversely affect our relationships with third party partners, employees, suppliers, customers and others with whom the REMI Business and we have business or other dealings or limit our ability to achieve the anticipated benefits of the Asset Transaction. If we are not able to successfully add the REMI Business to our existing business in an efficient, effective and timely manner, anticipated benefits, including the opportunities for growth we expect from the Asset Transaction, may not be realized fully, if at all, or may take longer to realize than expected, and our cash flow and financial condition may be negatively affected.

We will incur significant transaction costs in connection with the Asset Transaction.

We have incurred and expect to incur a number of non-recurring costs associated with the Asset Transaction, which could exceed the amounts currently estimated. These costs and expenses include financial advisory, legal, accounting, consulting and other advisory fees and expenses, filing fees and other related charges. There is also a large number of processes, policies, procedures, operations, technologies and systems that must be integrated in connection with the Asset Transaction. While we have assumed that a certain level of expenses would be incurred in connection with the Asset Transaction and the other transactions contemplated by the Purchase Agreement, there are many factors beyond our control that could affect the total amount or the timing of the integration and implementation expenses.

There may also be additional unanticipated significant costs in connection with the Asset Transaction that we may not recoup. These costs and expenses could reduce the benefits and additional income we expect to achieve from the Asset Transaction. Although we expect that these

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benefits will offset the transaction expenses and implementation costs over time, this net benefit may not be achieved in the near term or at all.

We are not providing pro forma financial statements reflecting the impact of the Asset Transaction on our historical operating results.

We do not expect to file a Current Report on Form 8-K with financial information for the REMI Business and pro forma financial statement information and, as a result, we are not including any pro forma financial statement information in this prospectus supplement. As a result, investors will be required to determine whether to participate in this offering without the benefit of the pro forma financial statement information.

It is possible that our experience in operating the REMI Business will require us to adjust our expectations regarding the impact of the Asset Transaction on our operating results.

Third parties may terminate or alter existing contracts or relationships with us or the REMI Business.

The REMI Business has contracts with customers, licensors and other business partners which may require the consent from these other parties in connection with the Asset Transaction. If these consents cannot be obtained, the REMI Business may suffer a loss of potential future revenue and may lose rights that are material to the REMI Business. In addition, third parties with which we or the REMI Business currently have relationships may terminate or otherwise reduce the scope of their relationships with either or both parties in connection with or as a result of the Asset Transaction. Any such disruptions could limit our ability to achieve the anticipated benefits of the Asset Transaction. The adverse effect of such disruptions could also be exacerbated by a delay in the completion of the Asset Transaction or the termination of the Asset Purchase Agreement.

We may have difficulty attracting, motivating and retaining key personnel and other employees in light of the Asset Transaction.

The REMI Business’ success after the Asset Transaction will depend in part on our ability to attract and retain key personnel and other employees. In connection with or as a result of the Asset Transaction, we may lose key personnel or may be unable to attract, retain and motivate qualified individuals, or the associated costs may increase. If we cannot retain employees of the REMI Business because of uncertainty relating to the Asset Transaction or the difficulty of integration or for any other reason, our ability to realize the anticipated benefits of the Asset Transaction could be reduced, and it may have a material adverse impact on our business and operations.

Litigation and other legal proceedings could require the expenditure of substantial resources and distract our personnel from being able to integrate the REMI Business into our business in a manner that enhances its value proposition to clients and facilitates other growth opportunities.

We are and may become involved in various legal proceedings arising from our business activities. While management is not aware of any litigation matter that in and of itself would have a material adverse impact on our consolidated results of operations, cash flows or financial position, litigation is inherently unpredictable, and depending on the nature and timing of a proceeding, an unfavorable resolution could materially affect our future consolidated results of operations, cash flows or financial position in a particular period, as well as our ability to successfully integrate the REMI Business into our business. For example, we are subject, from time to time, to product liability claims, intellectual property claims and claims brought by our competitors, including with respect to the hiring of employees. Such litigation or other legal proceedings, with or without merit, is unpredictable, generally expensive and time consuming and likely to divert significant resources from our business and from our efforts to integrate the REMI Business. Furthermore, because of the discovery that is required in

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connection with certain litigation, there is a risk that some of our confidential information could be compromised by disclosure. In addition, there could be public announcements of the results of trials, hearings, motions or other interim proceedings or developments and, if securities analysts or investors perceive these results to be negative, it could have a substantial adverse effect on the price of our common stock.

Risks Relating to this Offering

We have broad discretion in the use of the net proceeds from this offering and may not use them effectively.

We have broad discretion in the application of the net proceeds from this offering and could spend the proceeds in ways that do not improve our results of operations or enhance the value of our common stock. While we currently intend to use a portion of the net proceeds from this offering to finance the consideration, transaction costs and post-closing integration and research and development costs related to the Asset Transaction, in the event the Asset Transaction does not close for any reason, we would likely use the net proceeds from this offering for general corporate purposes, including working capital, capital expenditures, continued research and development, acquisitions or debt repayment. Except as described herein with respect to the Asset Transaction, we have not allocated these net proceeds for any specific purposes. We might not be able to yield a significant return, if any, on any investment of these net proceeds. Stockholders will not have the opportunity to influence our management’s decisions on how to use the net proceeds, and our failure to apply the funds effectively could have a material adverse effect on our business, delay the development of our product candidates and cause the price of our common stock to decline.

You will experience immediate dilution in the net tangible book value per share of the common stock you purchase.

The offering price of the common stock offered pursuant to this prospectus supplement is higher than the net tangible book value per share of our common stock. Therefore, if you purchase shares of common stock in this offering, you will incur immediate dilution in the pro forma net tangible book value per share of common stock from the price per share that you pay for the common stock. See the section entitled “Dilution” below for a more detailed discussion of the dilution you will incur if you purchase shares in this offering.

You may experience future dilution as a result of future equity offerings.

To raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock at prices that may not be the same as the price per share in this offering. We may sell shares or other securities in any other offering at a price per share that is less than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of our common stock, or securities convertible or exchangeable into common stock, in future transactions may be higher or lower than the price per share paid by investors in this offering. We also expect to continue to utilize equity-based compensation. To the extent the warrants and options are exercised or we issue common stock, preferred stock, or securities such as warrants that are convertible into, exercisable or exchangeable for, our common stock or preferred stock in the future, you may experience further dilution.

We have never paid cash dividends on our capital stock, and we do not anticipate paying any cash dividends in the foreseeable future.

We have never declared or paid cash dividends on our capital stock. We currently intend to retain all available funds and any future earnings for use in the operation and expansion of our business and do not anticipate paying any cash dividends in the foreseeable future.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus and the SEC filings that are incorporated by reference into this prospectus supplement and the accompanying prospectus contain or incorporate by reference forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), that are based on our management’s beliefs and assumptions and on information currently available to our management. Forward-looking statements include information concerning our possible or assumed future results of operations, business strategies, financing plans, competitive position, industry environment, potential growth opportunities and the effects of competition. Forward-looking statements include statements that are not historical facts and can be identified by terms such as “anticipates, “believes,” “could,” “seeks, “estimates,” “expects,” “intends,” “may,” “plans,” “potential,” “predicts,” “projects,” “should,” “will,” “would” or similar expressions and the negatives of those terms.

Forward looking statements include statements regarding:

| ∎ |  | our estimates regarding anticipated operating losses, future revenue, expenses, capital requirements, uses and sources of cash and liquidity, including our anticipated revenue growth and cost savings;

| ∎ |  | our ability to achieve profitability, and the potential need to raise additional funding;

| ∎ |  | our ability to ensure that we have effective disclosure controls and procedures;

| ∎ |  | our ability to meet, and potential liability from not meeting, any outstanding commitments and contractual obligations;

| ∎ |  | our ability to maintain compliance with the quality requirements of the United States Food and Drug Administration and similar foreign regulatory requirements;

| ∎ |  | our ability to market, improve, grow, commercialize and achieve market acceptance of any of our products or any product candidates that we are developing or may develop in the future;

| ∎ |  | our ability to continue to enhance our product offerings, and to commercialize and achieve market acceptance of any of our products or product candidates;

| ∎ |  | the effect of any existing or future federal, state or international regulations on our ability to effectively conduct our business;

| ∎ |  | our business strategy and our underlying assumptions about market data, demographic trends, reimbursement trends and pricing trends;

| ∎ |  | our ability to maintain an adequate global sales network for our products, including to attract and retain independent sales agents and direct sales representatives;

| ∎ |  | our ability to increase the use and promotion of our products by training and educating spine surgeons and our global sales network;

| ∎ |  | our ability to attract and retain a qualified management team, as well as other qualified personnel and advisors, including in connection with the ongoing operation of the REMI Business;

| ∎ |  | our ability to enter into and/or maintain licensing and business combination agreements with third parties and to successfully integrate the acquired technology and/or businesses, including in connection with the acquisition of the REMI Business;

| ∎ |  | the extent to which we are able to realize the anticipated benefits of the Asset Transaction;

| ∎ |  | our ability to effectively manage the anticipated and any unanticipated costs related to the acquisition of the REMI Business;

| ∎ |  | the impact of global economic and political conditions and public health crises on our business and industry; and

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| ∎ |  | other factors discussed elsewhere in this prospectus supplement and accompanying prospectus or any document incorporated by reference herein or therein.

Although we believe that we have a reasonable basis for each forward-looking statement contained in this prospectus supplement, the accompanying prospectus and the SEC filings that are incorporated by reference into this prospectus supplement and the accompanying prospectus, we caution you that these statements are based on our projections of the future that are subject to known and unknown risks and uncertainties and other factors that may cause our actual results, level of activity, performance or achievements expressed or implied by these forward-looking statements, to differ. The sections in this prospectus supplement captioned “Risk Factors” and in the sections of our Annual Report on Form 10-K captioned “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and “Business,” and in the sections of our Quarterly Reports on Form 10-Q captioned “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” as well as other sections in such documents, discuss some of the factors that could contribute to these differences.

Other unknown or unpredictable factors also could harm our results. Consequently, actual results or developments anticipated by us may not be realized or, even if substantially realized, may not have the expected consequences to, or effects on, us. Given these uncertainties, prospective investors are cautioned not to place undue reliance on such forward-looking statements. Except as required by law, we undertake no obligation to update or revise publicly any of the forward-looking statements after the date of this prospectus supplement.

This prospectus supplement, the accompanying prospectus, and the documents incorporated by reference in this prospectus supplement contain market data that we obtained from industry sources, including independent industry publications. In presenting this information, we have also made assumptions based on such data and other similar sources and on our knowledge of, and our experience to date in, the markets for our products. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. While we believe the market data included in this prospectus supplement is generally reliable, such information is inherently imprecise. In addition, projections, assumptions and estimates of our future performance and the future performance of the industry in which we operate are necessarily subject to a high degree of uncertainty and risk due to a variety of factors, including those described under the heading “Risk Factors” in this prospectus supplement and “Item 1A—Risk Factors” of our most recent report on Form 10-K or 10-Q which is incorporated by reference in this prospectus supplement. These and other factors could cause results to differ materially from those expressed in the estimates made by the independent parties and by us.

All forward-looking statements are based on information available to us on the date of this prospectus supplement and we will not update any of the forward-looking statements after the date of this prospectus supplement, except as required by law. Our actual results could differ materially from those discussed in this prospectus supplement. The forward-looking statements contained in this prospectus supplement, and other written and oral forward-looking statements made by us from time to time, are subject to certain risks and uncertainties that could cause actual results to differ materially from those anticipated in the forward-looking statements. Factors that might cause such a difference include, but are not limited to, those discussed in the following discussion and within the section of this prospectus supplement captioned “Risk Factors” beginning on page S-6, as well as the risk factors contained in the documents incorporated by reference to this prospectus supplement.

In addition, statements that “we believe” and similar statements reflect our beliefs and opinions on the relevant subject. These statements are based upon information available to us as of the date of this prospectus, and although we believe such information forms a reasonable basis for such statements, such information may be limited or incomplete, and our statements should not be read to indicate that we have conducted a thorough inquiry into, or review of, all potentially available relevant information. These statements are inherently uncertain and investors are cautioned not to unduly rely upon these statements.

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USE OF PROCEEDS

We estimate that the net proceeds to us from this offering, after deducting underwriting discounts and commissions and estimated offering expenses payable by us, will be approximately $57.4 million.

We intend to use the net proceeds of this offering for general corporate purposes, which may include working capital, capital expenditures, acquisitions, or research and development, as well as costs related to the purchase and post-closing integration with Alphatec of the REMI Business and research and development activities related to the integrated business. We will not have any obligation to repurchase any or all of our shares of common stock sold in this offering. The amount and timing of our expenditures will depend on several factors, including cash flows from our operations and the anticipated growth of our business. Accordingly, our management will have broad discretion in the application of the net proceeds and investors will be relying on the judgment of our management regarding the application of the proceeds from this offering.

We reserve the right to change the use of these proceeds as a result of certain contingencies such as the results of our commercialization efforts, competitive developments, opportunities to acquire products, technologies or businesses and other factors.

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DIVIDEND POLICY

We have never declared or paid cash dividends on our capital stock. We currently intend to retain all available funds and any future earnings for use in the operation and expansion of our business and do not anticipate paying any cash dividends in the foreseeable future.

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DILUTION

If you invest in our common stock, your interest will be diluted immediately to the extent of any difference between the offering price per share you pay for shares of our common stock in this offering and the as adjusted net tangible book value per share of our common stock after this offering. Net tangible book value per share represents our total tangible assets less total liabilities, divided by the number of shares of our common stock outstanding, as of December 31, 2022.

As of December 31, 2022, our net tangible book value was a deficit of approximately $135.7 million, or $(1.27) per share of common stock. After giving effect to the sale of shares of common stock at the offering price of $14.00 per share and after deducting estimated underwriting discounts and commissions and estimated expenses payable by us, our net tangible book value deficit as of December 31, 2022 would have been approximately $78.3 million, or $(0.70) per share of common stock. This represents an immediate decrease in as adjusted net tangible book value deficit to existing stockholders of $0.57 per share and an immediate dilution to new investors purchasing common stock in this offering of $14.70 per share.

The following table illustrates this per share dilution to the new investors purchasing shares of common stock in this offering:

Offering price per share |  |  |  |  |  | $ | 14.00 |
Net tangible book value deficit per share at December 31, 2022 |  | $ | (1.27 | ) |  |  |  |
Decrease in net tangible book value deficit per share attributable to new investors purchasing shares in this offering |  | $ | 0.57 |  |  |  |  |
As adjusted net tangible book value deficit per share as of December 31, 2022 after giving effect to this offering |  |  |  |  |  | $ | (0.70) |
Dilution per share to new investors in this offering |  |  |  |  |  | $ | 14.70 |

The foregoing table and calculations are based on 106,639,647 shares of our common stock outstanding as of December 31, 2022 and excludes:

| ∎ |  | 2,915,827 shares of common stock issuable upon exercise of options outstanding as of December 31, 2022, at a weighted average exercise price of $3.38 per share;

| ∎ |  | 15,490,610 shares of common stock issuable upon exercise of warrants outstanding as of December 31, 2022 at a weighted average exercise price of $3.32 share;

| ∎ |  | 8,533,273 shares of common stock issuable upon the vesting of restricted stock units outstanding as of December 31, 2022;

| ∎ |  | 17,245,619 shares of common stock issuable upon conversion of convertible notes outstanding as of December 31, 2022; and

| ∎ |  | 9,561,253 shares of common stock reserved for future issuance under stock-based compensation plans as of December 31, 2022, including 118,514 shares of common stock reserved for issuance under our Amended and Restated 2007 Employee Stock Purchase Plan, 1,268,514 shares of common stock reserved for issuance under our Amended and Restated 2016 Employee Inducement Award Plan, 7,619,000 shares of common stock reserved for future issuance under our 2017 Development Services Plan, 281,000 shares of common stock reserved for future issuance under our 2017 Distributor Inducement Plan, and 274,225 shares of common stock reserved for future issuance under our 2019 Management Objective Incentive Plan.

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To the extent that outstanding options are exercised, outstanding restricted stock units are settled, new options are issued under our equity incentive plans, or we otherwise issue additional shares of common stock in the future, you may experience further dilution. We may choose to raise additional capital due to market conditions or strategic considerations even if at that time we believe we have sufficient funds for our current or future operating plans. To the extent that additional capital is raised through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

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CERTAIN MATERIAL U.S. FEDERAL INCOME AND ESTATE TAX

CONSIDERATIONS FOR NON-U.S. HOLDERS OF OUR COMMON STOCK

The following is a general discussion of the material U.S. federal income tax considerations and certain U.S. estate tax considerations applicable to Non-U.S. Holders (as defined below) relating to the purchase, ownership and disposition of our common stock issued pursuant to this offering, but does not purport to be a complete analysis of all potential tax effects, including any U.S. federal income tax considerations to the Company.

This discussion is based on current provisions of the Internal Revenue Code of 1986, as amended (“Code”), final, temporary and proposed Treasury regulations promulgated thereunder (“Treasury Regulations”), judicial decisions, published rulings and administrative pronouncements of the U.S. Internal Revenue Service (“IRS”), all in effect as of the date of this prospectus supplement and all of which are subject to change or to differing interpretation, possibly with retroactive effect. Any change could alter the tax consequences to Non-U.S. Holders described herein. There can be no assurance that the IRS will not challenge one or more of the tax consequences described herein.

This discussion is limited to Non-U.S. Holders that hold our common stock as a “capital asset” within the meaning of Section 1221 of the Code (generally, property held for investment). This discussion does not address all aspects of U.S. federal income and estate taxation that may be relevant to a particular Non-U.S. Holder in light of that Non-U.S. Holder’s individual circumstances nor does it address any aspects of U.S. state, local or non-U.S. taxes, the alternative minimum tax, or the unearned income Medicare contribution tax on net investment income. This discussion also does not consider any specific facts or circumstances that may apply to a Non-U.S. Holder and does not address the special tax rules applicable to particular Non-U.S. Holders, including, without limitation:

| ∎ |  | U.S. expatriates and former citizens or long-term residents of the United States;

| ∎ |  | banks, insurance companies and other financial institutions;

| ∎ |  | brokers or dealers or traders in securities;

| ∎ |  | partnerships or other entities or arrangements treated as partnerships for U.S. federal income tax purposes (and investors therein);

| ∎ |  | tax-exempt organizations or governmental organizations;

| ∎ |  | persons deemed to sell our common stock under constructive sale provisions of the Code;

| ∎ |  | tax-qualified retirement plans;

| ∎ |  | persons holding our common stock as part of a straddle, hedge or other risk reduction strategy or as part of a conversion transaction or other integrated investment;

| ∎ |  | “controlled foreign corporations,” “passive foreign investment companies,” and corporations that accumulate earnings to avoid U.S. federal income tax;

| ∎ |  | persons who hold or receive our common stock pursuant to the exercise of any employee stock option or otherwise as compensation;

| ∎ |  | persons subject to special tax accounting rules as a result of any item of gross income with respect to our common stock being taken into account in an applicable financial statement; and

| ∎ |  | “qualified foreign pension funds” as defined in Section 897(l)(2) of the Code and entities all of the interests of which are held by qualified foreign pension funds.

If a partnership (or other entity or arrangement treated as a partnership for U.S. federal income tax purposes) holds our common stock, the tax treatment of a partner therein will generally depend on the status of the partner and the activities of the partnership. Partners of a partnership holding our common stock should consult their tax advisors as to the particular U.S. federal income tax consequences applicable to them.

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THIS SUMMARY IS NOT INTENDED TO CONSTITUTE A COMPLETE DESCRIPTION OF ALL TAX CONSEQUENCES FOR NON-U.S. HOLDERS RELATING TO THE PURCHASE, OWNERSHIP AND DISPOSITION OF OUR COMMON STOCK. PROSPECTIVE HOLDERS OF OUR COMMON STOCK SHOULD CONSULT WITH THEIR TAX ADVISORS REGARDING THE TAX CONSEQUENCES TO THEM (INCLUDING THE APPLICATION AND EFFECT OF ANY STATE, LOCAL, NON-U.S. INCOME AND OTHER TAX LAWS) OF THE PURCHASE, OWNERSHIP AND DISPOSITION OF OUR COMMON STOCK.

For purposes of this discussion, a “Non-U.S. Holder” means a beneficial owner of our common stock (other than an entity or arrangement that is treated as a partnership for U.S. federal income tax purposes) that is not, for U.S. federal income tax purposes, any of the following:

| ∎ |  | an individual who is a citizen or resident of the United States;

| ∎ |  | a corporation (or other entity treated as a corporation for U.S. federal income tax purposes) created or organized in the United States or under the laws of the United States, any state thereof or the District of Columbia;

| ∎ |  | an estate, the income of which is includable in gross income for U.S. federal income tax purposes regardless of its source; or

| ∎ |  | a trust if (i) a court within the United States is able to exercise primary supervision over the administration of the trust and one or more “U.S. persons,” as defined under the Code, have the authority to control all substantial decisions of the trust or (ii) such trust has made a valid election to be treated as a U.S. person for U.S. federal income tax purposes.

Distributions

As discussed under “Dividend Policy” above, we do not expect to make distributions on our common stock in the foreseeable future. However, if we do make distributions of cash or property on our common stock, such distributions will constitute dividends for U.S. federal income tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. Amounts of distributions not treated as dividends for U.S. federal income tax purposes will first constitute a tax-free return of capital of the Non-U.S. Holder’s investment and be applied against and reduce a Non-U.S. Holder’s adjusted tax basis in its common stock, but not below zero. Any remaining excess will be treated as capital gain and will be treated as described below under “Gain on Sale or Other Disposition of Common Stock.” Any such distributions will also be subject to the discussions below under the headings “Foreign Account Tax Compliance Act” and “Backup Withholding, Information Reporting and Other Reporting Requirements.”

Subject to the discussion in the next paragraph regarding effectively connected income, dividends paid to a Non-U.S. Holder generally will be subject to withholding of U.S. federal income tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty between the United States and such holder’s country of residence.

Dividends we pay to a Non-U.S. Holder that are effectively connected with its conduct of a trade or business within the United States (and, if required by an applicable tax treaty, are attributable to a U.S. permanent establishment or a fixed base maintained by such Non-U.S. Holder) will generally be exempt from the U.S. federal withholding tax, as described above, if the Non-U.S. Holder complies with applicable certification and disclosure requirements (generally including provision of a valid IRS Form W-8ECI (or applicable successor form) certifying that the dividends are effectively connected with the Non-U.S. Holder’s conduct of a trade or business within the United States). Instead, such dividends generally will be subject to U.S. federal income tax on a net income basis, at regular U.S. federal income tax rates as would apply if such holder were a U.S. person (as defined in the Code). Any U.S.

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effectively connected income received by a Non-U.S. Holder that is classified as a corporation for U.S. federal income tax purposes, may also be subject to an additional “branch profits tax” at a rate of 30% (or such lower rate as may be specified by an applicable income tax treaty).

A Non-U.S. Holder of our common stock who claims the benefit of an applicable income tax treaty between the United States and such holder’s country of residence generally will be required to provide a properly executed IRS Form W-8BEN or W-8BEN-E (or successor form) and satisfy applicable certification and other requirements. Non-U.S. Holders are urged to consult their tax advisors regarding their entitlement to benefits under a relevant income tax treaty and the specific methods available to them to satisfy these requirements.

Gain on Sale or Other Disposition of Common Stock

Subject to the discussion below under the headings “Foreign Account Tax Compliance Act” and “Backup Withholding, Information Reporting and Other Reporting Requirements,” a Non-U.S. Holder generally will not be subject to U.S. federal income tax on any gain realized upon the sale or other taxable disposition of the Non-U.S. Holder’s shares of our common stock unless:

| ∎ |  | the gain is effectively connected with a trade or business carried on by the Non-U.S. Holder within the United States (and, if required by an applicable income tax treaty, is attributable to a U.S. permanent establishment or fixed base maintained by such Non-U.S. Holder);

| ∎ |  | the Non-U.S. Holder is an individual and is present in the United States for 183 days or more in the taxable year of disposition and certain other conditions are met; or

| ∎ |  | we are or have been a “U.S. real property holding corporation” for U.S. federal income tax purposes at any time within the shorter of the five-year period preceding such disposition or such Non-U.S. Holder’s holding period of our common stock, and, provided that our common stock is “regularly” traded in an established securities market within the meaning of applicable Treasury Regulations, the Non-U.S. Holder has held, directly or constructively, at any time during said period, more than 5% of our common stock.

Gain described in the first bullet point above generally will be subject to U.S. federal income tax on a net income tax basis, at regular U.S. federal income tax rates. If the Non-U.S. Holder is a non-U.S. corporation, the branch profits tax described above also may apply to such effectively connected gain. Gain described in the second bullet point above will be subject to a flat 30% tax (or such lower rate as may be specified by an applicable income tax treaty); provided that the such gain is derived from U.S. sources (which may be offset by certain U.S.-source capital losses, if any, even though the individual is not considered a resident of the United States, provided that the Non-U.S. Holder has timely filed U.S. federal income tax returns with respect to such losses). With respect to the third bullet point above, we believe that we are not, and we do not anticipate becoming a U.S. real property holding corporation for U.S. federal income tax purposes.

Foreign Account Tax Compliance Act

Withholding taxes may be imposed under Sections 1471 to 1474 of the Code and related Treasury Regulations and guidance (“FATCA”), on certain types of payments made to non-U.S. financial institutions and certain other non-U.S. entities. Specifically, a 30% withholding tax may be imposed on dividends on our common stock paid to a “foreign financial institution” or a “non-financial foreign entity” (each as defined in the Code), unless (1) the foreign financial institution undertakes certain diligence and reporting obligations, (2) the non-financial foreign entity either certifies it does not have any “substantial United States owners” (as defined in the Code) or furnishes identifying information regarding each substantial United States owner, or (3) the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from these rules. If the payee is a foreign financial

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institution and is subject to the diligence and reporting requirements in (1) above, it must enter into an agreement with the U.S. Department of the Treasury requiring, among other things, that it undertake to identify accounts held by certain “specified United States persons” or “United States-owned foreign entities” (each as defined in the Code), annually report certain information about such accounts, and withhold 30% on certain payments to non-compliant foreign financial institutions and certain other account holders. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to different rules.

Under the applicable Treasury Regulations and administrative guidance, withholding under FATCA generally applies to payments of dividends on our common stock. While withholding under FATCA would have also applied to payments of gross proceeds from the sale or other disposition of stock on or after January 1, 2019, recently proposed Treasury Regulations eliminate FATCA withholding on payments of gross proceeds entirely. Taxpayers generally may rely on these proposed Treasury Regulations until final Treasury Regulations are issued.

Prospective investors should consult their tax advisors regarding the potential application of withholding under FATCA to their investment in our common stock.

Backup Withholding, Information Reporting and Other Reporting Requirements

We must report annually to the IRS and to each Non-U.S. Holder the amount of any distributions paid to, and the tax withheld with respect to, each Non-U.S. Holder. These reporting requirements apply regardless of whether withholding was reduced or eliminated by an applicable income tax treaty. Copies of this information reporting may also be made available under the provisions of a specific income tax treaty or agreement with the tax authorities in the country in which the Non-U.S. Holder resides or is established.

A Non-U.S. Holder will generally be subject to backup withholding for dividends on our common stock paid to such holder unless such holder certifies under penalties of perjury that, among other things, it is a Non-U.S. Holder (provided that the payor does not have actual knowledge or reason to know that such holder is a U.S. person) or otherwise establishes an exemption.

Information reporting and backup withholding generally will apply to the proceeds of a disposition of our common stock by a Non-U.S. Holder effected by or through the U.S. office of any broker, U.S. or non-U.S., unless the holder certifies its status as a Non-U.S. Holder and satisfies certain other requirements, or otherwise establishes an exemption. Generally, information reporting and backup withholding will not apply to a payment of disposition proceeds to a Non-U.S. Holder where the transaction is effected outside the United States through a non-U.S. office of a broker. However, for information reporting purposes, dispositions effected through a non-U.S. office of a broker with substantial U.S. ownership or operations generally will be treated in a manner similar to dispositions effected through a U.S. office of a broker. Non-U.S. Holder should consult their tax advisors regarding the application of the information reporting and backup withholding rules to them.

Backup withholding is not an additional income tax. Any amounts withheld under the backup withholding rules from a payment to a Non-U.S. Holder generally can be credited against the Non-U.S. Holder’s U.S. federal income tax liability, if any, or refunded, provided that the required information is furnished to the IRS in a timely manner. Non-U.S. Holder should consult their tax advisors regarding the application of the information reporting and backup withholding rules to them.

U.S. Federal Estate Tax

Shares of our common stock that are owned or treated as owned by an individual who is not a citizen or resident of the United States (as specially defined for U.S. federal estate tax purposes) at the

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time of death are considered U.S. situs assets and will be included in the individual’s gross estate for U.S. federal estate tax purposes. Such shares, therefore, may be subject to U.S. federal estate tax, unless an applicable estate tax or other treaty provides otherwise.

The preceding discussion of material U.S. federal income tax considerations and certain U.S. estate tax considerations is for information only. It is not legal or tax advice. Prospective investors should consult their tax advisors regarding the particular U.S. federal, state, local and non-U.S. tax consequences of purchasing, owning and disposing of our common stock, including the consequences of any proposed changes in applicable laws.

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UNDERWRITING

We have entered into an underwriting agreement with respect to the common stock being offered. Subject to the terms and conditions of the underwriting agreement, each underwriter has severally agreed to purchase from us the number of shares of our common stock set forth opposite its name below. Cowen and Company, LLC is the underwriter.

Underwriter |  | Number of Shares |
Cowen and Company, LLC |  |  | 4,285,715 |
Total |  |  | 4,285,715 |

The underwriting agreement provides that the obligations of the underwriter is subject to certain conditions precedent and that the underwriter has agreed to purchase all of the shares sold under the underwriting agreement if any of these shares are purchased.

We have agreed to indemnify the underwriter against specified liabilities, including liabilities under the Securities Act of 1933, and to contribute to payments the underwriter may be required to make in respect thereof.

The underwriter is offering the shares, subject to prior sale, when, as and if issued to and accepted by it, subject to approval of legal matters by their counsel and other conditions specified in the underwriting agreement. The underwriter reserves the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part.

Discounts and Commissions. The following table shows the offering price, underwriting discounts and commissions and proceeds, before expenses to us.

We estimate that the total expenses of the offering, excluding underwriting discounts and commissions, will be approximately $500,000 and are payable by us. We have agreed to reimburse the underwriter for up to $30,000 for their FINRA counsel fee and up to $200,000 for fees and disbursements of legal counsel to the underwriter. In accordance with FINRA Rule 5110, this reimbursed fee is deemed underwriting compensation for this offering.

|  | Per Share |  |  | Total |
Offering price |  | $ | 14.00 |  |  | $ | 60,000,010 |
Underwriting discounts and commissions |  | $ | 0.49 |  |  | $ | 2,100,000 |
Proceeds, before expenses, to Company |  | $ | 13.51 |  |  | $ | 57,900,010 |

The underwriter proposes to offer the shares of common stock at the offering price set forth on the cover of this prospectus. The underwriter may offer the shares of common stock to securities dealers at the offering price less a concession not in excess of $0.294 per share. If all of the shares are not sold at the offering price, the underwriter may change the offering price and other selling terms.

Discretionary Accounts. The underwriter does not intend to confirm sales of the shares to any accounts over which it has discretionary authority.

Our common stock is listed on the Nasdaq Global Select Market under the symbol “ATEC”.

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Stabilization. In connection with this offering, the underwriter may engage in stabilizing transactions, penalty bids and purchases to cover positions created by short sales.

| ∎ |  | Stabilizing transactions permit bids to purchase shares of common stock so long as the stabilizing bids do not exceed a specified maximum, and are engaged in for the purpose of preventing or retarding a decline in the market price of the common stock while the offering is in progress.

| ∎ |  | Penalty bids permit the representative to reclaim a selling concession from a syndicate member when the common stock originally sold by that syndicate member is purchased in stabilizing or syndicate covering transactions to cover syndicate short positions.

These stabilizing transactions, syndicate covering transactions and penalty bids may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of our common stock. As a result, the price of our common stock in the open market may be higher than it would otherwise be in the absence of these transactions. Neither we nor the underwriter make any representation or prediction as to the effect that the transactions described above may have on the price of our common stock. These transactions may be effected on the Nasdaq Stock Market, in the over-the-counter market or otherwise and, if commenced, may be discontinued at any time.

Passive Market Making. In connection with this offering, the underwriter and selling group members may engage in passive market making transactions in our common stock on the Nasdaq Stock Market in accordance with Rule 103 of Regulation M under the Securities Exchange Act of 1934, as amended, during a period before the commencement of offers or sales of common stock and extending through the completion of the distribution. A passive market maker must display its bid at a price not in excess of the highest independent bid of that security. However, if all independent bids are lowered below the passive market maker’s bid, such bid must then be lowered when specified purchase limits are exceeded.

Lock-Up Agreements.

We and our directors, officers have agreed that, without the prior written consent of Cowen and Company, LLC, we will not and they will not publicly disclose an intention to, during the period ending 90 days after the date of this prospectus (the “restricted period”):

| ∎ |  | offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend or otherwise transfer or dispose of, directly or indirectly, any shares of common stock or any securities convertible into or exercisable or exchangeable for shares of common stock; or

| ∎ |  | enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the common stock; whether any such transaction described above is to be settled by delivery of common stock or such other securities, in cash or otherwise. In addition, we have agreed that we will not file any registration statement with the Securities and Exchange Commission relating to the offering of any shares of common stock or any securities convertible into or exercisable or exchangeable for common stock, subject to certain exceptions, and each such other person agrees that, without the prior written consent of Cowen and Company, LLC, such other person will not, during the restricted period, make any demand for, or exercise any right with respect to, the registration of any shares of common stock or any security convertible into or exercisable or exchangeable for common stock.

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The restrictions described in the immediately preceding paragraph do not apply to:

| ∎ |  | transactions by a security holder relating to shares of common stock or other securities acquired in open market transactions after the completion of this offering; provided that no filing under Section 16(a) of the Exchange Act is required or voluntarily made during the restricted period in connection with subsequent sales of common stock or other securities acquired in such open market transactions;

| ∎ |  | transfers of shares of common stock or any security convertible into or exercisable or exchangeable for common stock (i) as a bona fide gift, (ii) to any trust for the direct or indirect benefit of the transferor or the immediate family of the transferor, (iii) if the transferor is a corporation, partnership, limited liability company, trust or other business entity (1) transfers to another corporation, partnership, limited liability company, trust or other business entity that is a direct or indirect affiliate of the transferor or (2) distributions of shares of common stock or any security convertible into or exercisable for common stock to limited partners, limited liability company members or stockholders of the transferor, (iv) if the transferor is a trust, to the beneficiary of such trust or (iv) transfers by testate succession or intestate succession, provided in each case that (a) such transfer does not involve disposition for value, (b) each distributee or transferee signs and delivers a lock-up agreement and (c) no filing under Section 16(a) of the Exchange Act reporting a reduction in beneficial ownership of shares of common stock shall be required or voluntarily made in connection with such transfer during the restricted period;

| ∎ |  | the establishment of any contract, instruction or trading plan pursuant to Rule 10b5-1 under the Exchange Act for the transfer of shares of common stock, provided that (i) such plan does not provide for the transfer of common stock during the restricted period and (ii) no public announcement of the establishment or existence thereof or filing under the Exchange Act, if any, is required of or voluntarily made by or on behalf of the person or us regarding the establishment of such plan during the restricted period;

| ∎ |  | the sale of shares by certain of our directors and executive officers in accordance with trading plans established pursuant to Rule 10b5-1 under the Exchange Act and existing as of the date of this prospectus supplement;

| ∎ |  | the exercise of options to purchase shares of common stock granted under any stock incentive plan or stock purchase plan described in this prospectus, provided that (i) the underlying shares shall continue to be subject to the restrictions on transfer set forth in the lock-up agreement and (ii) any filing under Section 16 of the Exchange Act made during the restricted period shall clearly indicate that (A) the filing relates to the circumstances described above and (B) no securities were sold by the person, and (iii) the person does not otherwise voluntarily effect any other public filing or report regarding such transfers during the restricted period;

| ∎ |  | the receipt from us of shares of common stock upon (i) the exercise or settlement of options or restricted stock units granted under a stock incentive plan or other equity award plan, which plan is described in this prospectus or (ii) the exercise of warrants outstanding and which are described in this prospectus;

| ∎ |  | the filing of a registration statement on Form S-8 to register common stock issuable pursuant to any employee benefit plans, qualified stock option plans or other employee compensation plans described in this prospectus;

| ∎ |  | the sale or issue shares of our common stock not to exceed 5% of our outstanding common stock in connection with any merger, joint venture, strategic alliance, commercial or other collaborative transaction or the acquisition or license of the business, property, technology or other assets of another individual or entity or the assumption of an employee benefit plan in connection with a merger or acquisition (including the filing of a registration statement on Form S-4 or other appropriate form with respect thereto); or

| ∎ |  | the sale of shares of common stock to the underwriter pursuant to the underwriting agreement.

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Cowen and Company, LLC, in its sole discretion, may release our common stock and other securities subject to the lock-up agreements described above in whole or in part at any time. When determining whether or not to release our common stock and other securities from lock-up agreements, Cowen and Company, LLC will consider, among other factors, the holder’s reasons for requesting the release, the number of shares for which the release is being requested and market conditions at the time of the request.

It is expected that delivery of the shares of common stock will be made against payment therefor on or about April 21, 2023, which is the first business day following the date hereof (such settlement cycle being referred to as “T+1”) and that investors in this offering will agree expressly to T+1 settlement as required by Rule 15c6-1 under the Securities Exchange Act of 1934, as amended.

Selling Restrictions

Canada. The common stock may be sold only to purchasers purchasing, or deemed to be purchasing, as principal that are accredited investors, as defined in National Instrument 45-106 Prospectus Exemptions or subsection 73.3(1) of the Securities Act (Ontario), and are permitted clients, as defined in National Instrument 31-103 Registration Requirements, Exemptions and Ongoing Registrant Obligations. Any resale of the common stock must be made in accordance with an exemption from, or in a transaction not subject to, the prospectus requirements of applicable securities laws.

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if this prospectus supplement (including any amendment thereto) contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

Pursuant to section 3A.3 of National Instrument 33-105 Underwriting Conflicts (NI 33-105), the underwriter is not required to comply with the disclosure requirements of NI 33-105 regarding underwriter conflicts of interest in connection with this offering.

Switzerland. The securities will not be offered, directly or indirectly, to the public in Switzerland and this prospectus does not constitute a public offering prospectus as that term is understood pursuant to article 652a or 1156 of the Swiss Federal Code of Obligations.

European Economic Area. In relation to each Member State of the European Economic Area (each, a “Member State”), no shares have been offered or will be offered pursuant to the offering to the public in that Member State prior to the publication of a prospectus in relation to the shares which has been approved by the competent authority in that Member State or, where appropriate, approved in another Member State and notified to the competent authority in that Member State, all in accordance with the Prospectus Regulation, except that shares may be offered to the public in that Member State at any time:

A. to any legal entity which is a qualified investor as defined under Article 2 the Prospectus Regulation;

B. to fewer than 150 natural or legal persons (other than qualified investors as defined under Article 2 the Prospectus Regulation), subject to obtaining the prior consent of the representative for any such offer; or

C. in any other circumstances falling within Article 1(4) of the Prospectus Regulation,

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provided that no such offer of the shares shall require us or any representative to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the Prospectus Regulation.

For the purposes of this provision, the expression an “offer to the public” in relation to shares in any Member State means the communication in any form and by any means of sufficient information on the terms of the offer and any shares to be offered so as to enable an investor to decide to purchase or subscribe for any shares, and the expression “Prospectus Regulation” means Regulation (EU) 2017/1129.

United Kingdom. No shares have been offered or will be offered pursuant to the offering to the public in the United Kingdom prior to the publication of a prospectus in relation to the shares which has been approved by the Financial Conduct Authority, except that the shares may be offered to the public in the United Kingdom at any time:

A. to any legal entity which is a qualified investor as defined under Article 2 of the UK Prospectus Regulation;

B. to fewer than 150 natural or legal persons (other than qualified investors as defined under Article 2 of the UK Prospectus Regulation), subject to obtaining the prior consent of the representative for any such offer; or

C. in any other circumstances falling within Section 86 of the FSMA,

provided that no such offer of the shares shall require the Issuer or any Manager to publish a prospectus pursuant to Section 85 of the FSMA or supplement a prospectus pursuant to Article 23 of the UK Prospectus Regulation. For the purposes of this provision, the expression an “offer to the public” in relation to the shares in the United Kingdom means the communication in any form and by any means of sufficient information on the terms of the offer and any shares to be offered so as to enable an investor to decide to purchase or subscribe for any shares and the expression “UK Prospectus Regulation” means Regulation (EU) 2017/1129 as it forms part of domestic law by virtue of the European Union (Withdrawal) Act 2018.

Hong Kong. The shares have not been offered or sold and will not be offered or sold in Hong Kong, by means of any document, other than (a) to “professional investors” as defined in the Securities and Futures Ordinance (Cap. 571 of the Laws of Hong Kong) (the “SFO”) of Hong Kong and any rules made thereunder; or (b) in other circumstances which do not result in the document being a “prospectus” as defined in the Companies (Winding Up and Miscellaneous Provisions) Ordinance (Cap. 32) of Hong Kong) (the “CO”), or which do not constitute an offer to the public within the meaning of the CO. No advertisement, invitation or document relating to the shares has been or may be issued or has been or may be in the possession of any person for the purposes of issue, whether in Hong Kong or elsewhere, which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to shares which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” as defined in the SFO and any rules made thereunder.

Singapore. Each underwriter has acknowledged that this prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, each underwriter has represented and agreed that it has not offered or sold any shares or caused the shares to be made the subject of an invitation for subscription or purchase and will not offer or sell any shares or cause the shares to be made the subject of an invitation for subscription or purchase, and has not circulated or distributed, nor will it circulate or distribute, this prospectus or any other document or material in connection with the

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offer or sale, or invitation for subscription or purchase, of the shares, whether directly or indirectly, to any person in Singapore other than:

A. to an institutional investor (as defined in Section 4A of the Securities and Futures Act (Chapter 289) of Singapore, as modified or amended from time to time (the “SFA”)) pursuant to Section 274 of the SFA;

B. to a relevant person (as defined in Section 275(2) of the SFA) pursuant to Section 275(1) of the SFA, or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions specified in Section 275 of the SFA; or

C. otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the shares are subscribed or purchased under Section 275 of the SFA by a relevant person which is:

A. a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or

B. a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary of the trust is an individual who is an accredited investor, securities or securities-based derivatives contracts (each term as defined in Section 2(1) of the SFA) of that corporation or the beneficiaries’ rights and interest (however described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the shares pursuant to an offer made under Section 275 of the SFA except:

(i) to an institutional investor or to a relevant person, or to any person arising from an offer referred to in Section 275(1A) or Section 276(4)(i)(B) of the SFA;

(ii) where no consideration is or will be given for the transfer;

(iii) where the transfer is by operation of law;

(iv) as specified in Section 276(7) of the SFA; or

(v) as specified in Regulation 37A of the Securities and Futures (Offers of Investments) (Securities and Securities-based Derivatives Contracts) Regulations 2018.

Singapore SFA Product Classification — In connection with Section 309B of the SFA and the CMP Regulations 2018, unless otherwise specified before an offer of shares, we have determined, and hereby notify all relevant persons (as defined in Section 309A(1) of the SFA), that the shares are “prescribed capital markets products” (as defined in the CMP Regulations 2018) and Excluded Investment Products (as defined in MAS Notice SFA 04-N12: Notice on the Sale of Investment Products and MAS Notice FAA-N16: Notice on Recommendations on Investment Products).

Israel. In the State of Israel this prospectus supplement shall not be regarded as an offer to the public to purchase shares of common stock under the Israeli Securities Law, 5728 – 1968, which requires a prospectus to be published and authorized by the Israel Securities Authority, if it complies with certain provisions of Section 15 of the Israeli Securities Law, 5728 – 1968, including, inter alia, if:

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(i) the offer is made, distributed or directed to not more than 35 investors, subject to certain conditions (the “Addressed Investors”); or (ii) the offer is made, distributed or directed to certain qualified investors defined in the First Addendum of the Israeli Securities Law, 5728 – 1968, subject to certain conditions (the “Qualified Investors”). The Qualified Investors shall not be taken into account in the count of the Addressed Investors and may be offered to purchase securities in addition to the 35 Addressed Investors. The company has not and will not take any action that would require it to publish a prospectus in accordance with and subject to the Israeli Securities Law, 5728 – 1968. We have not and will not distribute this prospectus or make, distribute or direct an offer to subscribe for our common stock to any person within the State of Israel, other than to Qualified Investors and up to 35 Addressed Investors.

Qualified Investors may have to submit written evidence that they meet the definitions set out in of the First Addendum to the Israeli Securities Law, 5728 – 1968. In particular, we may request, as a condition to be offered common stock, that Qualified Investors will each represent, warrant and certify to us and/or to anyone acting on our behalf: (i) that it is an investor falling within one of the categories listed in the First Addendum to the Israeli Securities Law, 5728 – 1968; (ii) which of the categories listed in the First Addendum to the Israeli Securities Law, 5728 – 1968 regarding Qualified Investors is applicable to it; (iii) that it will abide by all provisions set forth in the Israeli Securities Law, 5728 – 1968 and the regulations promulgated thereunder in connection with the offer to be issued common stock; (iv) that the shares of common stock that it will be issued are, subject to exemptions available under the Israeli Securities Law, 5728 – 1968: (a) for its own account; (b) for investment purposes only; and (c) not issued with a view to resale within the State of Israel, other than in accordance with the provisions of the Israeli Securities Law, 5728 – 1968; and (v) that it is willing to provide further evidence of its Qualified Investor status. Addressed Investors may have to submit written evidence in respect of their identity and may have to sign and submit a declaration containing, inter alia, the Addressed Investor’s name, address and passport number or Israeli identification number.

We have not authorized and do not authorize the making of any offer of securities through any financial intermediary on our behalf, other than offers made by the underwriter and its affiliates, with a view to the final placement of the securities as contemplated in this document. Accordingly, no purchaser of the shares, other than the underwriter, is authorized to make any further offer of shares on our behalf or on behalf of the underwriter.

Electronic Offer, Sale and Distribution of Shares. A prospectus in electronic format may be made available on the websites maintained by the underwriter or selling group members, if any, participating in this offering and the underwriter participating in this offering may distribute prospectuses electronically. The underwriter may agree to allocate a number of shares to the underwriter and selling group members for sale to their online brokerage account holders. Internet distributions will be allocated by the underwriter and selling group members that will make internet distributions on the same basis as other allocations. Other than the prospectus in electronic format, the information on these websites is not part of this prospectus or the registration statement of which this prospectus forms a part, has not been approved or endorsed by us or any underwriter in its capacity as underwriter, and should not be relied upon by investors.

Other Relationships. The underwriter and its affiliates have provided, and may in the future provide, various investment banking, commercial banking and other financial services for us and our affiliates for which they have received, and may in the future receive, customary fees. In addition, we entered into an at-the-market offering program sales agreement with Cowen and Company, LLC on August 6, 2020, pursuant to which, we may offer and sell, from time to time at our discretion, shares of our common stock having an aggregate offering price of up to $50 million through Cowen and Company, LLC as our sales agent, for which Cowen and Company, LLC has received customary fees and expenses.

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LEGAL MATTERS

Dentons Durham Jones Pinegar P.C., St. George, Utah will pass upon the validity of the securities offered by this prospectus supplement. Certain legal matters will be passed upon on behalf of the underwriter by Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., Boston, Massachusetts.

EXPERTS

The consolidated financial statements of Alphatec Holdings, Inc. as of December 31, 2022 and 2021, and for each of the two years in the period ended December 31, 2022, incorporated by reference in this prospectus supplement, and the effectiveness of Alphatec Holdings, Inc.’s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such consolidated financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

The consolidated The consolidated statement of operations, comprehensive loss, stockholders’ equity and cash flows of Alphatec Holdings, Inc. as of December 31, 2020, and for the year ended December 31, 2020, incorporated by reference in this prospectus supplement to Alphatec Holdings, Inc.’s annual report on Form 10-K for the year ended December 31, 2022, have been audited by Mayer Hoffman McCann P.C., an independent registered public accounting firm, as stated in their reports. Such consolidated financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

WHERE YOU CAN FIND ADDITIONAL INFORMATION

We file annual, quarterly and other reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at http://www.sec.gov. Our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K, including any amendments to those reports, and other information that we file with or furnish to the SEC pursuant to Section 13(a) or 15(d) of the Exchange Act can also be accessed free of charge by linking directly from our website at http://www.atecspine.com under “Investor Relations—Financial Information—SEC Filings” caption. These filings will be available as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. Information contained on our website is not part of this prospectus supplement.

You should rely only on the information provided in, and incorporated by reference in, this prospectus supplement and the accompanying prospectus and the registration statement. We have not authorized anyone else to provide you with different information. Our securities are not being offered in any state where the offer is not permitted. The information contained in documents that are incorporated by reference in this prospectus supplement is accurate only as of the dates of those documents. Our business, financial condition, results of operations and prospects may have changed since those dates.

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INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to incorporate by reference the information we file with it, which means that we can disclose important information to you by referring you to another document that we have filed separately with the SEC. You should read the information incorporated by reference herein because it is an important part of this prospectus supplement. We incorporate by reference the following information or documents that we have filed with the SEC (excluding those portions of any Form 8-K that are not deemed “filed” pursuant to the General Instructions of Form 8-K):

| ∎ |  | our Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on February 28, 2023;

| ∎ |  | the information specifically incorporated by reference into our Annual Report on Form 10-K from our Definitive Proxy Statement on Schedule 14A filed with the SEC on April 28, 2022;

| ∎ |  | our Current Reports on Form 8-K filed with the SEC on January 9, 2023 and April 19, 2023 (except for the information furnished and not expressly filed under Items 2.02 or 7.01 and the exhibits thereto which are furnished and not expressly filed); and

| ∎ |  | the description of our Common Stock contained in our Registration Statement on Form 8-A filed pursuant to Section 12(b) of the Exchange Act as filed with SEC on May 26, 2006, as updated by Exhibit 4.15 to our Annual Report on Form 10-K for the year ended December 31, 2020 and including any other amendments or reports filed for the purpose of updating such description.

All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering will also be incorporated by reference into this prospectus supplement and deemed to be part of this prospectus supplement from the date of the filing of such reports and documents; provided, however, we are not incorporating by reference any documents or portions thereof, whether specifically listed above or filed in the future, that are not deemed “filed” with the SEC, including our Compensation Committee report and performance graph or any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K.

Any statement contained in any document incorporated by reference herein shall be deemed to be modified or superseded for purposes of this prospectus supplement to the extent that a statement contained in this prospectus supplement modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus supplement.

We will provide without charge to each person, including any beneficial owner, to whom this prospectus supplement is delivered, upon written or oral request, a copy of any or all documents that are incorporated by reference into this prospectus supplement, but not delivered with this prospectus supplement, other than exhibits to such documents unless such exhibits are specifically incorporated by reference into the documents that this prospectus supplement incorporates. You should direct written requests to: Alphatec Holdings, Inc., Attn: Corporate Secretary, 1950 Camino Vida Roble, Carlsbad, California 92008, or you may call us at (760) 431-9286.

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PROSPECTUS

Common Stock

Preferred Stock

Debt Securities

Warrants

Units

We may offer and sell the securities identified above from time to time in one or more offerings. This prospectus provides you with a general description of the securities.

Each time we offer and sell securities, we will provide a supplement to this prospectus that contains specific information about the offering and the amounts, prices and terms of the securities. The supplement may also add, update or change information contained in this prospectus with respect to that offering. You should carefully read this prospectus and the applicable prospectus supplement before you invest in any of our securities.

We may offer and sell the securities described in this prospectus and any prospectus supplement to or through one or more underwriters, dealers and agents, or directly to purchasers, or through a combination of these methods. If any underwriters, dealers or agents are involved in the sale of any of the securities, their names and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. See the sections of this prospectus entitled “About this Prospectus” and “Plan of Distribution” for more information. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.

Investing in our securities involves risks. See the “Risk Factors” beginning on page 5 of this prospectus and any similar section contained in the applicable prospectus supplement and the documents incorporated herein or therein by reference concerning factors you should consider before investing in our securities.

Our common stock is listed on The Nasdaq Global Select Market under the symbol “ATEC.” On April 18, 2023, the last reported sale price of our common stock on The Nasdaq Global Select Market was $15.69 per share.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is April 19, 2023.

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TABLE OF CONTENTS

ABOUT THIS PROSPECTUS |  |  | 1 |
WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE |  |  | 2 |
ABOUT ALPHATEC |  |  | 4 |
RISK FACTORS |  |  | 5 |
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS |  |  | 6 |
USE OF PROCEEDS |  |  | 7 |
DESCRIPTION OF CAPITAL STOCK |  |  | 8 |
DESCRIPTION OF DEBT SECURITIES |  |  | 13 |
DESCRIPTION OF WARRANTS |  |  | 21 |
DESCRIPTION OF UNITS |  |  | 23 |
GLOBAL SECURITIES |  |  | 24 |
PLAN OF DISTRIBUTION |  |  | 27 |
LEGAL MATTERS |  |  | 29 |
EXPERTS |  |  | 29 |

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ABOUT THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the U.S. Securities and Exchange Commission, or the SEC, as a “well-known seasoned issuer” as defined in Rule 405 under the Securities Act of 1933, as amended, using a “shelf” registration process. By using a shelf registration statement, we may sell any combination of the securities described in this prospectus from time to time and in one or more offerings as described in this prospectus. Each time that we offer and sell securities, we will provide a prospectus supplement to this prospectus that contains specific information about the securities being offered and sold and the specific terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information related to these offerings. The prospectus supplement or free writing prospectus may also add, update or change information contained in this prospectus with respect to that offering. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement or free writing prospectus, you should rely on the prospectus supplement or free writing prospectus, as applicable. Before purchasing any securities, you should carefully read both this prospectus and the applicable prospectus supplement (and any applicable free writing prospectuses), together with the additional information described under the heading “Where You Can Find More Information; Incorporation by Reference.”

This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

You should rely only on the information contained in or incorporated by reference in this prospectus or any related prospectus supplement. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. We will not make an offer to sell these securities in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus and the applicable prospectus supplement to this prospectus is accurate only as of the date on its respective cover, and that any information incorporated by reference is accurate only as of the date of the document incorporated by reference, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have changed since those dates. This prospectus incorporates by reference, and any prospectus supplement or free writing prospectus may contain and incorporate by reference, market data and industry statistics and forecasts that are based on independent industry publications and other publicly available information. Although we believe these sources are reliable, we do not guarantee the accuracy or completeness of this information and we have not independently verified this information. In addition, the market and industry data and forecasts that may be included or incorporated by reference in this prospectus, any prospectus supplement or any applicable free writing prospectus may involve estimates, assumptions and other risks and uncertainties and are subject to change based on various factors, including those discussed under the heading “Risk Factors” contained in this prospectus, the applicable prospectus supplement and any applicable free writing prospectus, and under similar headings in other documents that are incorporated by reference into this prospectus. Accordingly, investors should not place undue reliance on this information.

When we refer to “Alphatec,” “we,” “our,” “us” and the “Company” in this prospectus, we mean Alphatec Holdings, Inc. and its consolidated subsidiaries, unless otherwise specified. “Alphatec Spine” refers to our wholly owned operating subsidiary Alphatec Spine, Inc. “SafeOp” refers to our wholly owned operating subsidiary SafeOp Surgical, Inc. “EOS” refers to our wholly owned operating subsidiary EOS imaging S.A. When we refer to “you,” we mean the potential holders of the applicable series of securities.

The Alphatec name and logo and the names of products and services offered by Alphatec, Alphatec Spine, SafeOp and EOS are trademarks, registered trademarks, service marks or registered service marks of Alphatec. All other trademarks, trade names and service marks appearing in this prospectus or the documents incorporated by reference herein are the property of their respective owners. Use or display by us of other parties’ trademarks, trade dress or products is not intended to and does not imply a relationship with, or endorsements or sponsorship of, us by the trademark or trade dress owner. Solely for convenience, trademarks and tradenames referred to in this prospectus appear without the ® and ™ symbols, but those references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or that the applicable owner will not assert its rights, to these trademarks and tradenames.

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WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE

Available Information

We file reports, proxy statements and other information with the SEC. The SEC also maintains a web site that contains reports, proxy and information statements and other information about issuers, such as us, who file electronically with the SEC. The address of that website is http://www.sec.gov.

Our web site address is www.atecspine.com. The information on our web site, however, is not, and should not be deemed to be, a part of this prospectus.

This prospectus and any prospectus supplement are part of a registration statement that we filed with the SEC and do not contain all of the information in the registration statement. The full registration statement may be obtained from the SEC or us, as provided below. Forms of the indenture and other documents establishing the terms of the offered securities are or may be filed as exhibits to the registration statement. Statements in this prospectus or any prospectus supplement about these documents are summaries and each statement is qualified in all respects by reference to the document to which it refers. You should refer to the actual documents for a more complete description of the relevant matters. You may inspect a copy of the registration statement through the SEC’s website, as provided above.

Incorporation by Reference

The SEC’s rules allow us to “incorporate by reference” information into this prospectus and any accompanying prospectus supplement, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, and subsequent information that we file with the SEC will automatically update and supersede that information. Any statement contained in a previously filed document incorporated by reference will be deemed to be modified or superseded for purposes of this prospectus and any accompanying prospectus supplement to the extent that a statement contained in this prospectus modifies or replaces that statement.

We incorporate by reference our documents listed below and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act, between the date of this prospectus and the termination of the offering of the securities described in this prospectus. We are not, however, incorporating by reference any documents or portions thereof, whether specifically listed below or filed in the future, that are not deemed “filed” with the SEC, including our Compensation Committee report and performance graph or any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K.

This prospectus and any accompanying prospectus supplement incorporate by reference the documents set forth below that have previously been filed with the SEC:

| • |  | our Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on February 28, 2023;

| • |  | The information specifically incorporated by reference into our Annual Report on Form 10-K from our Definitive Proxy Statement on Schedule 14A filed with the SEC on April 28, 2022;

| • |  | our Current Reports on Form 8-K filed with the SEC on January 9, 2023 and April 19, 2023 (except for the information furnished and not expressly filed under Items 2.02 or 7.01 and the exhibits thereto which are furnished and not expressly filed); and

| • |  | the description of our Common Stock contained in our Registration Statement on Form 8-A filed pursuant to Section 12(b) of the Exchange Act as filed with SEC on May 26, 2006, as updated by Exhibit 4.15 to our Annual Report on Form 10-K for the year ended December 31, 2020 and including any other amendments or reports filed for the purpose of updating such description.

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All reports and other documents we subsequently file pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act prior to the termination of this offering, including all such documents we may file with the SEC after the date of the initial registration statement and prior to the effectiveness of the registration statement, but excluding any information furnished to, rather than filed with, the SEC, will also be incorporated by reference into this prospectus and deemed to be part of this prospectus from the date of the filing of such reports and documents.

You may request a free copy of any of the documents incorporated by reference in this prospectus (other than exhibits, unless they are specifically incorporated by reference in the documents) by writing or telephoning us at the following address:

Alphatec Holdings, Inc.

Attn: Corporate Secretary

1950 Camino Vida Roble

Carlsbad, CA 92008

(760) 431-9286

Exhibits to the filings will not be sent, however, unless those exhibits have specifically been incorporated by reference in this prospectus and any accompanying prospectus supplement.

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ABOUT ALPHATEC

We are a medical technology company focused on the design, development, and advancement of technology for better surgical treatment of spinal disorders. Through our wholly owned subsidiaries, Alphatec Spine, SafeOp and EOS, our mission is to revolutionize the approach to spine surgery through clinical distinction. We are focused on developing new approaches that integrate seamlessly with our expanding Alpha InformatiX™ product platform to better inform surgery and to achieve the goal of spine surgery more predictably and reproducibly. We have a broad product portfolio designed to address the spine’s various pathologies. Our ultimate vision is to be the standard bearer in spine.

Alphatec Holdings, Inc. is a Delaware corporation incorporated in March 2005. Our principal executive office is located at 1950 Camino Vida Roble, Carlsbad, California 92008, and our telephone number is (760) 431-9286.

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RISK FACTORS

Investment in any securities offered pursuant to this prospectus and the applicable prospectus supplement involves risks. You should carefully consider the risk factors incorporated by reference to our most recent Annual Report on Form 10-K and our subsequent Quarterly Reports on Form 10-Q or Current Reports on Form 8-K we file after the date of this prospectus, and all other information contained or incorporated by reference into this prospectus, as updated by our subsequent filings under the Exchange Act, and the risk factors and other information contained in the applicable prospectus supplement before acquiring any of such securities. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus and the documents incorporated by reference herein contain forward-looking statements. All statements other than statements of historical facts contained in this prospectus and the documents incorporated by reference herein are forward-looking statements. These statements involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. This prospectus and the documents incorporated by reference herein also contain estimates and other statistical data made by independent parties and by us relating to market size and growth and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.

In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplates,” “believes,” “estimates,” “predicts,” “potential” or “continue” or the negative of these terms or other similar expressions. The forward-looking statements in this prospectus and the documents incorporated by reference herein are only predictions. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our business, financial condition and results of operations. These forward-looking statements speak only as of the date of this prospectus or that of any document incorporated herein by reference and are subject to a number of risks, uncertainties and assumptions, including those under “Risk Factors” and elsewhere in this prospectus and in the applicable prospectus supplement and the documents incorporated by reference herein. The events and circumstances reflected in our forward-looking statements may not be achieved or occur and actual results could differ materially from those projected in the forward-looking statements. Moreover, we operate in an evolving environment. New risk factors and uncertainties may emerge from time to time, and it is not possible for management to predict all risk factors and uncertainties. Except as required by applicable law, we do not plan to publicly update or revise any forward-looking statements contained in this prospectus or the documents incorporated by reference herein, whether as a result of any new information, future events, changed circumstances or otherwise.

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USE OF PROCEEDS

We intend to use the net proceeds from the sale of the securities as set forth in the applicable prospectus supplement.

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DESCRIPTION OF CAPITAL STOCK

The following description of our capital stock is not complete and may not contain all the information you should consider before investing in our capital stock. This description is summarized from, and qualified in its entirety by reference to, our amended and restated certificate of incorporation, which has been publicly filed with the SEC. See “Where You Can Find More Information; Incorporation by Reference.”

Our authorized capital stock consists of:

| • |  | 200,000,000 shares of common stock, $0.0001 par value; and

| • |  | 20,000,000 shares of preferred stock, $0.0001 par value.

Common Stock

As of April 17, 2023, there were 113,705,989 shares of our common stock outstanding.

Voting Rights

For all matters submitted to a vote of stockholders, each holder of our common stock is entitled to one vote for each share registered in his or her name. Except as may be required by law and in connection with some significant actions, such as mergers, consolidations, or amendments to our amended and restated certificate of incorporation that affect the rights of stockholders, holders of our common stock vote together as a single class. There is no cumulative voting in the election of our directors, which means that, subject to any rights to elect directors that are granted to the holders of any class or series of preferred stock, a plurality of the votes cast at a meeting of stockholders at which a quorum is present is sufficient to elect a director.

Dividend Rights

Subject to preferential dividend rights of any other class or series of stock, the holders of shares of our common stock are entitled to receive dividends, including dividends of our stock, as and when declared by our board of directors, subject to any limitations applicable by law and to the rights of the holders, if any, of our preferred stock.

Liquidation

In the event we are liquidated, dissolved or our affairs are wound up, after we pay or make adequate provision for all of our known debts and liabilities, each holder of our common stock will be entitled to share ratably in all assets that remain, subject to any rights that are granted to the holders of any class or series of preferred stock.

Other Rights and Preferences

Subject to the preferential rights of any other class or series of stock, all shares of our common stock have equal dividend, distribution, liquidation and other rights, and have no preference, appraisal or exchange rights, except for any appraisal rights provided by Delaware law. Furthermore, holders of our common stock have no conversion, sinking fund or redemption rights, or preemptive rights to subscribe for any of our securities. Our amended and restated certificate of incorporation and restated bylaws do not restrict the ability of a holder of our common stock to transfer his or her shares of our common stock.

The rights, powers, preferences and privileges of holders of our common stock are subject to, and may be adversely affected by, the rights of holders of shares of any series of preferred stock which we may designate and issue in the future.

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Transfer Agent and Registrar

The transfer agent for our common stock is Computershare, Inc.

Preferred Stock

Under our amended and restated certificate of incorporation, we have authority, subject to any limitations prescribed by law and without further stockholder approval, to issue from time to time up to 20,000,000 shares of preferred stock in one or more series and to fix the rights, preferences, privileges, qualifications and restrictions granted to or imposed upon the preferred stock, including dividend rights, conversion rights, voting rights, rights and terms of redemption, liquidation preference and sinking fund terms, any or all of which may be greater than the rights of the common stock.

Series A Convertible Preferred Stock

In March 2017, we created a new class of preferred stock designated as Series A Convertible Preferred Stock. The rights of the Series A Convertible Preferred Stock are set forth in a Certificate of Designation filed with the Secretary of State of Delaware on March 22, 2018. A total of 15,245 shares of Series A Convertible Preferred Stock are authorized for issuance under such Certificate of Designation. The shares of Series A Convertible Preferred Stock have a stated value of $1,000 per share and are convertible into shares of our common stock at an initial conversion price of $2.00 per share. No shares of Series A Convertible Preferred Stock are outstanding as of April 17, 2023.

Holders of the Series A Convertible Preferred Stock are entitled to dividends on an as-if-converted basis in the same form as any dividends actually paid on shares of our common stock.

Series B Convertible Preferred Stock

In March 2018, we created a new class of preferred stock designated as Series B Convertible Preferred Stock. The rights of the Series B Convertible Preferred Stock are set forth in a Certificate of Designation filed with the Secretary of State of Delaware on March 8, 2018. All of the shares of Series B Convertible Preferred Stock were converted into shares of our common stock in May 2018. No shares of Series B Convertible Preferred Stock are outstanding as of April 17, 2023.

New Redeemable Preferred Stock

To date, our board of directors has designated 15,000,000 of the 20,000,000 authorized shares of preferred stock as new redeemable preferred stock.

We issued shares of redeemable preferred stock in connection with our initial public offering in June 2006. As of April 17, 2023, 3,319,816 shares of new redeemable preferred stock were issued and outstanding. The new redeemable preferred stock is not convertible into common stock but is redeemable at $9.00 per share (subject to appropriate adjustment in the event of any stock dividend, stock split, combination or other similar recapitalization affecting such shares) (i) upon our liquidation, dissolution or winding up, or the occurrence of certain mergers, consolidations or sales of all or substantially all of our assets, before any payment to the holders of our common stock, or (ii) at our option at any time. Holders of new redeemable preferred stock are generally not entitled to vote on matters submitted to the stockholders, except with respect to certain matters that will affect them adversely as class, and are not entitled to receive dividends.

The issuance of preferred stock could adversely affect the voting power of holders of common stock and reduce the likelihood that common stockholders will receive dividend payments and payments upon liquidation. The issuance could have the effect of decreasing the market price of our common stock. The issuance of preferred stock also could have the effect of delaying, deterring or preventing a change in control of our company.

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Our board of directors will fix the rights, preferences, privileges, qualifications and restrictions of the preferred stock of each series that we sell under this prospectus and applicable prospectus supplements in the certificate of designation relating to that series. We will incorporate by reference into the registration statement of which this prospectus is a part the form of any certificate of designation that describes the terms of the series of preferred stock we are offering before the issuance of the related series of preferred stock. This description will include:

| • |  | the title and stated value;

| • |  | the number of shares we are offering;

| • |  | the liquidation preference per share;

| • |  | the purchase price per share;

| • |  | the dividend rate per share, dividend period and payment dates and method of calculation for dividends;

| • |  | whether dividends will be cumulative or non-cumulative and, if cumulative, the date from which dividends will accumulate;

| • |  | our right, if any, to defer payment of dividends and the maximum length of any such deferral period;

| • |  | the procedures for any auction and remarketing, if any;

| • |  | the provisions for a sinking fund, if any;

| • |  | the provisions for redemption or repurchase, if applicable, and any restrictions on our ability to exercise those redemption and repurchase rights;

| • |  | any listing of the preferred stock on any securities exchange or market;

| • |  | whether the preferred stock will be convertible into our common stock or other securities of ours, including depositary shares and warrants, and, if applicable, the conversion period and the conversion price or how the conversion price will be calculated, and under what circumstances it may be adjusted;

| • |  | whether the preferred stock will be exchangeable into debt securities, and, if applicable, the exchange period and the exchange price or how the exchange price will be calculated, and under what circumstances it may be adjusted;

| • |  | voting rights, if any, of the preferred stock;

| • |  | preemption rights, if any;

| • |  | restrictions on transfer, sale or other assignment, if any;

| • |  | whether interests in the preferred stock will be represented by depositary shares;

| • |  | a discussion of any material or special U.S. federal income tax considerations applicable to the preferred stock;

| • |  | the relative ranking and preferences of the preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs;

| • |  | any limitations on issuances of any class or series of preferred stock ranking senior to or on a parity with the series of preferred stock being issued as to dividend rights and rights if we liquidate, dissolve or wind up our affairs; and

| • |  | any other specific terms, rights, preferences, privileges, qualifications or restrictions of the preferred stock.

When we issue shares of our preferred stock under this prospectus, the shares will be fully paid and nonassessable and, unless specified in the applicable prospectus supplement, will not have or be subject to any rights of first refusal or similar rights.

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The Delaware General Corporation Law, or the DGCL, the state of our incorporation, provides that the holders of preferred stock will have the right to vote separately as a class on any proposal involving fundamental changes in the rights of holders of that preferred stock. This right is in addition to any voting rights that may be provided for in the applicable certificate of designation.

Anti-Takeover Effects of Delaware Law and Our Certificate of Incorporation and Bylaws

We are subject to the provisions of Section 203 of the DGCL. Under Section 203, we would generally be prohibited from engaging in any business combination with any interested stockholder for a period of three years following the time that this stockholder became an interested stockholder unless:

| • |  | prior to this time, the board of directors of the corporation approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder;

| • |  | upon consummation of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding shares owned by persons who are directors and also officers, and by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

| • |  | at or subsequent to such time, the business combination is approved by the board of directors and authorized at an annual or special meeting of stockholders, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock that is not owned by the interested stockholder.

Under Section 203, a “business combination” includes:

| • |  | any merger or consolidation involving the corporation and the interested stockholder;

| • |  | any sale, transfer, pledge or other disposition of 10% or more of the assets of the corporation involving the interested stockholder;

| • |  | any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder, subject to limited exceptions;

| • |  | any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder; or

| • |  | the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

In general, Section 203 defines an interested stockholder as an entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by such entity or person.

Certain provisions of our amended and restated certificate of incorporation and restated bylaws that are summarized below may be deemed to have an anti-takeover effect and may delay, deter or prevent a tender offer or takeover attempt that a stockholder might consider to be in its best interests, including attempts that might result in a premium being paid over the market price for the shares held by stockholders. Furthermore, these provisions could delay, until the next stockholders’ meeting, actions which are favored by the holders of a majority of our outstanding voting securities.

Among other things, our amended and restated certificate of incorporation and restated bylaws provide that:

| • |  | subject to the rights of the holders of any class or series of preferred stock then outstanding, our directors may be removed only by the affirmative vote of the holders of at least a majority of the voting

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| power of all of the then outstanding shares then entitled to vote at an election of directors voting together as a single class, unless otherwise specified by law or by the amended and restated certificate of incorporation;

| • |  | any vacancy on our board of directors, however occurring, including a vacancy resulting from an enlargement of the board, may only be filled by vote of a majority of the directors then in office, even if less than a quorum, or by a sole remaining director, and not by the stockholders;

| • |  | stockholder action may be taken only at a duly called and convened annual or special meeting of stockholders and then only if properly brought before the meeting;

| • |  | stockholder action may not be taken by written action in lieu of a meeting;

| • |  | special meetings of stockholders may be called only by our board of directors pursuant to a resolution adopted by a majority of the total number of directors; and

| • |  | in order for any matter to be considered “properly brought” before a meeting, a stockholder must comply with requirements regarding specified information and advance notice to us.

Our amended and restated certificate of incorporation also provides that no director of our company shall be personally liable for any monetary damages for any breach of fiduciary duty as a director, except for liability (i) for any breach of the director’s duty of loyalty to the company or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL, or (iv) for any transaction from which the director derived an improper personal benefit. Our amended and restated certificate of incorporation also provides that if the DGCL is amended to authorize corporate action further eliminating or limiting the personal liability of directors, then the liability of a director of our company shall be eliminated or limited to the fullest extent permitted by the DGCL, as so amended. Our amended and restated certificate of incorporation further provides that no amendment to or repeal of these provisions shall apply to or have any effect on the liability or alleged liability of any director for or with respect to any acts or omissions of such director occurring prior to such amendment or repeal. Our amended and restated certificate of incorporation further provides for the indemnification of our directors and officers to the fullest extent permitted by the DGCL.

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DESCRIPTION OF DEBT SECURITIES

The following description, together with the additional information we include in any applicable prospectus supplement, summarizes certain general terms and provisions of the debt securities that we may offer under this prospectus. When we offer to sell a particular series of debt securities, we will describe the specific terms of the series in a supplement to this prospectus. We will also indicate in the supplement to what extent the general terms and provisions described in this prospectus apply to a particular series of debt securities.

We may issue debt securities either separately, or together with, or upon the conversion or exercise of or in exchange for, other securities described in this prospectus. Debt securities may be our senior, senior subordinated or subordinated obligations and, unless otherwise specified in a supplement to this prospectus, the debt securities will be our direct, unsecured obligations and may be issued in one or more series.

The debt securities will be issued under an indenture between us and a trustee named in the prospectus supplement. We have summarized select portions of the indenture below. The summary is not complete. The form of the indenture has been filed as an exhibit to the registration statement and you should read the indenture for provisions that may be important to you. In the summary below, we have included references to the section numbers of the indenture so that you can easily locate these provisions. Capitalized terms used in the summary and not defined herein have the meanings specified in the indenture.

As used in this section only, “Alphatec,” “we,” “our” or “us” refer to Alphatec Holdings, Inc. excluding our subsidiaries, unless expressly stated or the context otherwise requires.

General

The terms of each series of debt securities will be established by or pursuant to a resolution of our board of directors and set forth or determined in the manner provided in a resolution of our board of directors, in an officer’s certificate or by a supplemental indenture. (Section 2.2) The particular terms of each series of debt securities will be described in a prospectus supplement relating to such series (including any pricing supplement or term sheet).

We can issue an unlimited amount of debt securities under the indenture that may be in one or more series with the same or various maturities, at par, at a premium, or at a discount. (Section 2.1) We will set forth in a prospectus supplement (including any pricing supplement or term sheet) relating to any series of debt securities being offered, the aggregate principal amount and the following terms of the debt securities, if applicable:

| • |  | the title and ranking of the debt securities (including the terms of any subordination provisions);

| • |  | the price or prices (expressed as a percentage of the principal amount) at which we will sell the debt securities;

| • |  | any limit on the aggregate principal amount of the debt securities;

| • |  | the date or dates on which the principal on a particular series of debt securities is payable;

| • |  | the rate or rates (which may be fixed or variable) per annum or the method used to determine the rate or rates (including any commodity, commodity index, stock exchange index or financial index) at which the debt securities will bear interest, the date or dates from which interest will accrue, the date or dates on which interest will commence and be payable and any regular record date for the interest payable on any interest payment date;

| • |  | the place or places where principal of, and interest, if any, on the debt securities will be payable (and the method of such payment), where the debt securities of such series may be surrendered for registration of transfer or exchange, and where notices and demands to us in respect of the debt securities may be delivered;

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| • |  | the period or periods within which, the price or prices at which and the terms and conditions upon which we may redeem the debt securities;

| • |  | any obligation we have to redeem or purchase the debt securities pursuant to any sinking fund or analogous provisions or at the option of a holder of debt securities and the period or periods within which, the price or prices at which and in the terms and conditions upon which securities of the series shall be redeemed or purchased, in whole or in part, pursuant to such obligation;

| • |  | the dates on which and the price or prices at which we will repurchase debt securities at the option of the holders of debt securities and other detailed terms and provisions of these repurchase obligations;

| • |  | the denominations in which the debt securities will be issued, if other than denominations of $1,000 and any integral multiple thereof;

| • |  | whether the debt securities will be issued in the form of certificated debt securities or global debt securities;

| • |  | the portion of principal amount of the debt securities payable upon declaration of acceleration of the maturity date, if other than the principal amount;

| • |  | the currency of denomination of the debt securities, which may be U.S. Dollars or any foreign currency, and if such currency of denomination is a composite currency, the agency or organization, if any, responsible for overseeing such composite currency;

| • |  | the designation of the currency, currencies or currency units in which payment of principal of, and premium and interest on, the debt securities will be made;

| • |  | if payments of principal of, or premium or interest on, the debt securities will be made in one or more currencies or currency units other than that or those in which the debt securities are denominated, the manner in which the exchange rate with respect to these payments will be determined;

| • |  | the manner in which the amounts of payment of principal of, and premium, if any, and interest on the debt securities will be determined, if these amounts may be determined by reference to an index based on a currency or currencies or by reference to a commodity, commodity index, stock exchange index or financial index;

| • |  | any provisions relating to any security provided for the debt securities;

| • |  | any addition to, deletion of or change in the Events of Default described in this prospectus or in the indenture with respect to the debt securities and any change in the acceleration provisions described in this prospectus or in the indenture with respect to the debt securities;

| • |  | any addition to, deletion of or change in the covenants described in this prospectus or in the indenture with respect to the debt securities;

| • |  | any depositaries, interest rate calculation agents, exchange rate calculation agents or other agents with respect to the debt securities;

| • |  | the provisions, if any, relating to conversion or exchange of any debt securities of such series, including if applicable, the conversion or exchange price and period, provisions as to whether conversion or exchange will be mandatory, the events requiring an adjustment of the conversion or exchange price and provisions affecting conversion or exchange;

| • |  | any other terms of the debt securities, which may supplement, modify or delete any provision of the indenture as it applies to that series, including any terms that may be required under applicable law or regulations or advisable in connection with the marketing of the securities; and

| • |  | whether any of our direct or indirect subsidiaries will guarantee the debt securities of that series, including the terms of subordination, if any, of such guarantees. (Section 2.2)

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We may issue debt securities that provide for an amount less than their stated principal amount to be due and payable upon declaration of acceleration of their maturity pursuant to the terms of the indenture. We will provide you with information on the federal income tax considerations and other special considerations applicable to any of these debt securities in the applicable prospectus supplement.

If we denominate the purchase price of any of the debt securities in a foreign currency or currencies or a foreign currency unit or units, or if the principal of, and any premium, and interest on, any series of debt securities is payable in a foreign currency or currencies or a foreign currency unit or units, we will provide you with information on the restrictions, elections, general tax considerations, specific terms and other information with respect to that issue of debt securities and such foreign currency or currencies or foreign currency unit or units in the applicable prospectus supplement.

Transfer and Exchange

Each debt security will be represented by either one or more global securities registered in the name of The Depository Trust Company, or the DTC or the Depositary, or a nominee of the Depositary (we will refer to any debt security represented by a global debt security as a “book-entry debt security”), or a certificate issued in definitive registered form (we will refer to any debt security represented by a certificated security as a “certificated debt security”) as set forth in the applicable prospectus supplement. Except as set forth under the heading “Global Debt Securities and Book-Entry System” below, book-entry debt securities will not be issuable in certificated form.

Certificated Debt Securities. You may transfer or exchange certificated debt securities at any office we maintain for this purpose in accordance with the terms of the indenture. (Section 2.4) No service charge will be made for any transfer or exchange of certificated debt securities, but we may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection with a transfer or exchange. (Section 2.7)

You may effect the transfer of certificated debt securities and the right to receive the principal of, premium and interest on certificated debt securities only by surrendering the certificate representing those certificated debt securities and either reissuance by us or the trustee of the certificate to the new holder or the issuance by us or the trustee of a new certificate to the new holder.

Global Debt Securities and Book-Entry System. Each global debt security representing book-entry debt securities will be deposited with, or on behalf of, the Depositary, and registered in the name of the Depositary or a nominee of the Depositary. Please see “Global Securities.”

Covenants

We will set forth in the applicable prospectus supplement any restrictive covenants applicable to any issue of debt securities. (Article IV)

No Protection in the Event of a Change of Control

Unless we state otherwise in the applicable prospectus supplement, the debt securities will not contain any provisions which may afford holders of the debt securities protection in the event we have a change in control or in the event of a highly leveraged transaction (whether or not such transaction results in a change in control) which could adversely affect holders of debt securities.

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Consolidation, Merger and Sale of Assets

We may not consolidate with or merge with or into, or convey, transfer or lease all or substantially all of our properties and assets to, any person (a “successor person”) unless:

| • |  | we are the surviving corporation or the successor person (if other than Alphatec) is a corporation organized and validly existing under the laws of any U.S. domestic jurisdiction and expressly assumes our obligations on the debt securities and under the indenture; and

| • |  | immediately after giving effect to the transaction, no Default or Event of Default, shall have occurred and be continuing.

Notwithstanding the above, any of our subsidiaries may consolidate with, merge into or transfer all or part of its properties to us. (Section 5.1)

Events of Default

“Event of Default” means with respect to any series of debt securities, any of the following:

| • |  | default in the payment of any interest upon any debt security of that series when it becomes due and payable, and continuance of such default for a period of 30 days (unless the entire amount of the payment is deposited by us with the trustee or with a paying agent prior to the expiration of the 30-day period);

| • |  | default in the payment of principal of any debt security of that series at its maturity;

| • |  | default in the performance or breach of any other covenant or warranty by us in the indenture (other than a covenant or warranty that has been included in the indenture solely for the benefit of a series of debt securities other than that series), which default continues uncured for a period of 60 days after we receive written notice from the trustee or Alphatec and the trustee receive written notice from the holders of not less than 25% in principal amount of the outstanding debt securities of that series as provided in the indenture;

| • |  | certain voluntary or involuntary events of bankruptcy, insolvency or reorganization of Alphatec; or

| • |  | any other Event of Default provided with respect to debt securities of that series that is described in the applicable prospectus supplement. (Section 6.1)

No Event of Default with respect to a particular series of debt securities (except as to certain events of bankruptcy, insolvency or reorganization) necessarily constitutes an Event of Default with respect to any other series of debt securities. (Section 6.1) The occurrence of certain Events of Default or an acceleration under the indenture may constitute an event of default under certain indebtedness of ours or our subsidiaries outstanding from time to time.

We will provide the trustee written notice of any Default or Event of Default within 30 days of becoming aware of the occurrence of such Default or Event of Default, which notice will describe in reasonable detail the status of such Default or Event of Default and what action we are taking or propose to take in respect thereof. (Section 6.1)

If an Event of Default with respect to debt securities of any series at the time outstanding occurs and is continuing, then the trustee or the holders of not less than 25% in principal amount of the outstanding debt securities of that series may, by a notice in writing to us (and to the trustee if given by the holders), declare to be due and payable immediately the principal of (or, if the debt securities of that series are discount securities, that portion of the principal amount as may be specified in the terms of that series) and accrued and unpaid interest, if any, on all debt securities of that series. In the case of an Event of Default resulting from certain events of bankruptcy, insolvency or reorganization, the principal (or such specified amount) of and accrued and unpaid

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interest, if any, on all outstanding debt securities will become and be immediately due and payable without any declaration or other act on the part of the trustee or any holder of outstanding debt securities. At any time after a declaration of acceleration with respect to debt securities of any series has been made, but before a judgment or decree for payment of the money due has been obtained by the trustee, the holders of a majority in principal amount of the outstanding debt securities of that series may rescind and annul the acceleration if all Events of Default, other than the non-payment of accelerated principal and interest, if any, with respect to debt securities of that series, have been cured or waived as provided in the indenture. (Section 6.2) We refer you to the prospectus supplement relating to any series of debt securities that are discount securities for the particular provisions relating to acceleration of a portion of the principal amount of such discount securities upon the occurrence of an Event of Default.

The indenture provides that the trustee may refuse to perform any duty or exercise any of its rights or powers under the indenture, unless the trustee receives indemnity satisfactory to it against any cost, liability or expense which might be incurred by it in performing such duty or exercising such right or power. (Section 7.1(e)) Subject to certain rights of the trustee, the holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee with respect to the debt securities of that series. (Section 6.12)

No holder of any debt security of any series will have any right to institute any proceeding, judicial or otherwise, with respect to the indenture or for the appointment of a receiver or trustee, or for any remedy under the indenture, unless:

| • |  | that holder has previously given to the trustee written notice of a continuing Event of Default with respect to debt securities of that series; and

| • |  | the holders of not less than 25% in principal amount of the outstanding debt securities of that series have made written request, and offered indemnity or security satisfactory to the trustee, to the trustee to institute the proceeding as trustee, and the trustee has not received from the holders of not less than a majority in principal amount of the outstanding debt securities of that series a direction inconsistent with that request and has failed to institute the proceeding within 60 days. (Section 6.7)

Notwithstanding any other provision in the indenture, the holder of any debt security will have an absolute and unconditional right to receive payment of the principal of, premium and any interest on, that debt security on or after the due dates expressed in that debt security and to institute suit for the enforcement of payment. (Section 6.8)

The indenture requires us, within 120 days after the end of our fiscal year, to furnish to the trustee a statement as to compliance with the indenture. (Section 4.3) If a Default or Event of Default occurs and is continuing with respect to the securities of any series and if it is known to a responsible officer of the trustee, the trustee shall mail to each holder of the securities of that series notice of a Default or Event of Default within 90 days after it occurs or, if later, after a responsible officer of the trustee has knowledge of such Default or Event of Default. The indenture provides that the trustee may withhold notice to the holders of debt securities of any series of any Default or Event of Default (except in payment on any debt securities of that series) with respect to debt securities of that series if the trustee determines in good faith that withholding notice is in the interest of the holders of those debt securities. (Section 7.5)

Modification and Waiver

We and the trustee may modify, amend or supplement the indenture or the debt securities of any series without the consent of any holder of any debt security:

| • |  | to cure any ambiguity, defect or inconsistency;

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| • |  | to comply with covenants in the indenture described above under the heading “Consolidation, Merger and Sale of Assets”;

| • |  | to provide for uncertificated securities in addition to or in place of certificated securities;

| • |  | to add guarantees with respect to debt securities of any series or secure debt securities of any series;

| • |  | to surrender any of our rights or powers under the indenture;

| • |  | to add covenants or events of default for the benefit of the holders of debt securities of any series;

| • |  | to comply with the applicable procedures of the applicable depositary;

| • |  | to make any change that does not adversely affect the rights of any holder of debt securities;

| • |  | to provide for the issuance of and establish the form and terms and conditions of debt securities of any series as permitted by the indenture;

| • |  | to effect the appointment of a successor trustee with respect to the debt securities of any series and to add to or change any of the provisions of the indenture to provide for or facilitate administration by more than one trustee; or

| • |  | to comply with requirements of the SEC in order to effect or maintain the qualification of the indenture under the Trust Indenture Act. (Section 9.1)

We may also modify and amend the indenture with the consent of the holders of at least a majority in principal amount of the outstanding debt securities of each series affected by the modifications or amendments. We may not make any modification or amendment without the consent of the holders of each affected debt security then outstanding if that amendment will:

| • |  | reduce the amount of debt securities whose holders must consent to an amendment, supplement or waiver;

| • |  | reduce the rate of or extend the time for payment of interest (including default interest) on any debt security;

| • |  | reduce the principal of or premium on or change the fixed maturity of any debt security or reduce the amount of, or postpone the date fixed for, the payment of any sinking fund or analogous obligation with respect to any series of debt securities;

| • |  | reduce the principal amount of discount securities payable upon acceleration of maturity;

| • |  | waive a default in the payment of the principal of, premium or interest on any debt security (except a rescission of acceleration of the debt securities of any series by the holders of at least a majority in aggregate principal amount of the then outstanding debt securities of that series and a waiver of the payment default that resulted from such acceleration);

| • |  | make the principal of or premium or interest on any debt security payable in currency other than that stated in the debt security;

| • |  | make any change to certain provisions of the indenture relating to, among other things, the right of holders of debt securities to receive payment of the principal of, and premium and interest on those debt securities and to institute suit for the enforcement of any such payment and to waivers or amendments; or

| • |  | waive a redemption payment with respect to any debt security. (Section 9.3)

Except for certain specified provisions, the holders of at least a majority in principal amount of the outstanding debt securities of any series may on behalf of the holders of all debt securities of that series waive our compliance with provisions of the indenture. (Section 9.2) The holders of a majority in principal amount of the

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outstanding debt securities of any series may on behalf of the holders of all the debt securities of such series waive any past default under the indenture with respect to that series and its consequences, except a default in the payment of the principal of, premium or any interest on any debt security of that series; provided, however, that the holders of a majority in principal amount of the outstanding debt securities of any series may rescind an acceleration and its consequences, including any related payment default that resulted from the acceleration. (Section 6.13)

Defeasance of Debt Securities and Certain Covenants in Certain Circumstances

Legal Defeasance. The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, we may be discharged from any and all obligations in respect of the debt securities of any series (subject to certain exceptions). We will be so discharged upon the irrevocable deposit with the trustee, in trust, of money and/or U.S. government obligations or, in the case of debt securities denominated in a single currency other than U.S. Dollars, government obligations of the government that issued or caused to be issued such currency, that, through the payment of interest and principal in accordance with their terms, will provide money or U.S. government obligations in an amount sufficient in the opinion of a nationally recognized firm of independent public accountants or investment bank to pay and discharge each installment of principal of, premium and interest on, and any mandatory sinking fund payments in respect of, the debt securities of that series on the stated maturity of those payments in accordance with the terms of the indenture and those debt securities.

This discharge may occur only if, among other things, we have delivered to the trustee an opinion of counsel stating that we have received from, or there has been published by, the United States Internal Revenue Service a ruling or, since the date of execution of the indenture, there has been a change in the applicable U.S. federal income tax law, in either case to the effect that, and based thereon such opinion shall confirm that, the holders of the debt securities of that series will not recognize income, gain or loss for U.S. federal income tax purposes as a result of the deposit, defeasance and discharge and will be subject to U.S. federal income tax on the same amounts and in the same manner and at the same times as would have been the case if the deposit, defeasance and discharge had not occurred. (Section 8.3)

Defeasance of Certain Covenants. The indenture provides that, unless otherwise provided by the terms of the applicable series of debt securities, upon compliance with certain conditions:

| • |  | we may omit to comply with the covenant described under the heading “Consolidation, Merger and Sale of Assets” and certain other covenants set forth in the indenture, as well as any additional covenants which may be set forth in the applicable prospectus supplement; and

| • |  | any omission to comply with those covenants will not constitute a Default or an Event of Default with respect to the debt securities of that series (“covenant defeasance”).

The conditions include:

| • |  | depositing with the trustee money and/or U.S. government obligations or, in the case of debt securities denominated in a single currency other than U.S. Dollars, government obligations of the government that issued or caused to be issued such currency, that, through the payment of interest and principal in accordance with their terms, will provide money in an amount sufficient in the opinion of a nationally recognized firm of independent public accountants or investment bank to pay and discharge each installment of principal of, premium and interest on and any mandatory sinking fund payments in respect of the debt securities of that series on the stated maturity of those payments in accordance with the terms of the indenture and those debt securities; and

| • |  | delivering to the trustee an opinion of counsel to the effect that we have received from, or there has been published by, the United States Internal Revenue Service a ruling or, since the date of execution of the indenture, there has been a change in the applicable U.S. federal income tax law, in either case to

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| the effect that, and based thereon such opinion shall confirm that, the holders of the debt securities of that series will not recognize income, gain or loss for U.S. federal income tax purposes as a result of the deposit and related covenant defeasance and will be subject to U.S. federal income tax on the same amounts and in the same manner and at the same times as would have been the case if the deposit and related covenant defeasance had not occurred. (Section 8.4)

No Personal Liability of Directors, Officers, Employees or Stockholders

None of our past, present or future directors, officers, employees or stockholders, as such, will have any liability for any of our obligations under the debt securities or the indenture or for any claim based on, or in respect or by reason of, such obligations or their creation. By accepting a debt security, each holder waives and releases all such liability. This waiver and release is part of the consideration for the issue of the debt securities. However, this waiver and release may not be effective to waive liabilities under U.S. federal securities laws, and it is the view of the SEC that such a waiver is against public policy.

Governing Law

The indenture and the debt securities, including any claim or controversy arising out of or relating to the indenture or the securities, will be governed by the laws of the State of New York.

The indenture will provide that we, the trustee and the holders of the debt securities (by their acceptance of the debt securities) irrevocably waive, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to the indenture, the debt securities or the transactions contemplated thereby.

The indenture will provide that any legal suit, action or proceeding arising out of or based upon the indenture or the transactions contemplated thereby may be instituted in the federal courts of the United States of America located in the City of New York or the courts of the State of New York in each case located in the City of New York, and we, the trustee and the holder of the debt securities (by their acceptance of the debt securities) irrevocably submit to the non-exclusive jurisdiction of such courts in any such suit, action or proceeding. The indenture will further provide that service of any process, summons, notice or document by mail (to the extent allowed under any applicable statute or rule of court) to such party’s address set forth in the indenture will be effective service of process for any suit, action or other proceeding brought in any such court. The indenture will further provide that we, the trustee and the holders of the debt securities (by their acceptance of the debt securities) irrevocably and unconditionally waive any objection to the laying of venue of any suit, action or other proceeding in the courts specified above and irrevocably and unconditionally waive and agree not to plead or claim any such suit, action or other proceeding has been brought in an inconvenient forum. (Section 10.10)

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DESCRIPTION OF WARRANTS

We may issue warrants for the purchase of shares of our common stock or preferred stock or of debt securities. We may issue warrants independently or together with other securities, and the warrants may be attached to or separate from any offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and the investors or a warrant agent. The following summary of material provisions of the warrants and warrant agreements is subject to, and qualified in its entirety by reference to, all the provisions of the warrant agreement and warrant certificate applicable to a particular series of warrants. The terms of any warrants offered under a prospectus supplement may differ from the terms described below. We urge you to read the applicable prospectus supplement and any related free writing prospectus, as well as the complete warrant agreements and warrant certificates that contain the terms of the warrants.

The particular terms of any issue of warrants will be described in the prospectus supplement relating to the issue. Those terms may include:

| • |  | the number of shares of common stock or preferred stock purchasable upon the exercise of warrants to purchase such shares and the price at which such number of shares may be purchased upon such exercise;

| • |  | the designation, stated value and terms (including, without limitation, liquidation, dividend, conversion and voting rights) of the series of preferred stock purchasable upon exercise of warrants to purchase preferred stock;

| • |  | the principal amount of debt securities that may be purchased upon exercise of a debt warrant and the exercise price for the warrants, which may be payable in cash, securities or other property;

| • |  | the date, if any, on and after which the warrants and the related debt securities, preferred stock or common stock will be separately transferable;

| • |  | the terms of any rights to redeem or call the warrants;

| • |  | the date on which the right to exercise the warrants will commence and the date on which the right will expire;

| • |  | U.S. federal income tax consequences applicable to the warrants; and

| • |  | any additional terms of the warrants, including terms, procedures, and limitations relating to the exchange, exercise and settlement of the warrants.

Holders of equity warrants will not be entitled to:

| • |  | vote, consent or receive dividends;

| • |  | receive notice as stockholders with respect to any meeting of stockholders for the election of our directors or any other matter; or

| • |  | exercise any rights as stockholders of Alphatec.

Each warrant will entitle its holder to purchase the principal amount of debt securities or the number of shares of preferred stock or common stock at the exercise price set forth in, or calculable as set forth in, the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to the specified time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

A holder of warrant certificates may exchange them for new warrant certificates of different denominations, present them for registration of transfer and exercise them at the corporate trust office of the warrant agent or any

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other office indicated in the applicable prospectus supplement. Until any warrants to purchase debt securities are exercised, the holder of the warrants will not have any rights of holders of the debt securities that can be purchased upon exercise, including any rights to receive payments of principal, premium or interest on the underlying debt securities or to enforce covenants in the applicable indenture. Until any warrants to purchase common stock or preferred stock are exercised, the holders of the warrants will not have any rights of holders of the underlying common stock or preferred stock, including any rights to receive dividends or payments upon any liquidation, dissolution or winding up on the common stock or preferred stock, if any.

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DESCRIPTION OF UNITS

We may issue units consisting of any combination of the other types of securities offered under this prospectus in one or more series. We may evidence each series of units by unit certificates that we will issue under a separate agreement. We may enter into unit agreements with a unit agent. Each unit agent will be a bank or trust company that we select. We will indicate the name and address of the unit agent in the applicable prospectus supplement relating to a particular series of units.

The following description, together with the additional information included in any applicable prospectus supplement, summarizes the general features of the units that we may offer under this prospectus. You should read any prospectus supplement and any free writing prospectus that we may authorize to be provided to you related to the series of units being offered, as well as the complete unit agreements that contain the terms of the units. Specific unit agreements will contain additional important terms and provisions and we will file as an exhibit to the registration statement of which this prospectus is a part, or will incorporate by reference from another report that we file with the SEC, the form of each unit agreement relating to units offered under this prospectus.

If we offer any units, certain terms of that series of units will be described in the applicable prospectus supplement, including, without limitation, the following, as applicable:

| • |  | the title of the series of units;

| • |  | identification and description of the separate constituent securities comprising the units;

| • |  | the price or prices at which the units will be issued;

| • |  | the date, if any, on and after which the constituent securities comprising the units will be separately transferable;

| • |  | a discussion of certain U.S. federal income tax considerations applicable to the units; and

| • |  | any other terms of the units and their constituent securities.

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GLOBAL SECURITIES

Book-Entry, Delivery and Form

Unless we indicate differently in a prospectus supplement, the securities initially will be issued in book-entry form and represented by one or more global notes or global securities, or, collectively, global securities. The global securities will be deposited with, or on behalf of, the DTC and registered in the name of Cede & Co., the nominee of DTC. Unless and until it is exchanged for individual certificates evidencing securities under the limited circumstances described below, a global security may not be transferred except as a whole by the depositary to its nominee or by the nominee to the depositary, or by the depositary or its nominee to a successor depositary or to a nominee of the successor depositary.

DTC has advised us that it is:

| • |  | a limited-purpose trust company organized under the New York Banking Law;

| • |  | a “banking organization” within the meaning of the New York Banking Law;

| • |  | a member of the Federal Reserve System;

| • |  | a “clearing corporation” within the meaning of the New York Uniform Commercial Code; and

| • |  | a “clearing agency” registered pursuant to the provisions of Section 17A of the Exchange Act.

DTC holds securities that its participants deposit with DTC. DTC also facilitates the settlement among its participants of securities transactions, such as transfers and pledges, in deposited securities through electronic computerized book-entry changes in participants’ accounts, thereby eliminating the need for physical movement of securities certificates. “Direct participants” in DTC include securities brokers and dealers, including underwriters, banks, trust companies, clearing corporations and other organizations. DTC is a wholly-owned subsidiary of The Depository Trust & Clearing Corporation, or DTCC. DTCC is the holding company for DTC, National Securities Clearing Corporation and Fixed Income Clearing Corporation, all of which are registered clearing agencies. DTCC is owned by the users of its regulated subsidiaries. Access to the DTC system is also available to others, which we sometimes refer to as indirect participants, that clear through or maintain a custodial relationship with a direct participant, either directly or indirectly. The rules applicable to DTC and its participants are on file with the SEC.

Purchases of securities under the DTC system must be made by or through direct participants, which will receive a credit for the securities on DTC’s records. The ownership interest of the actual purchaser of a security, which we sometimes refer to as a beneficial owner, is in turn recorded on the direct and indirect participants’ records. Beneficial owners of securities will not receive written confirmation from DTC of their purchases. However, beneficial owners are expected to receive written confirmations providing details of their transactions, as well as periodic statements of their holdings, from the direct or indirect participants through which they purchased securities. Transfers of ownership interests in global securities are to be accomplished by entries made on the books of participants acting on behalf of beneficial owners. Beneficial owners will not receive certificates representing their ownership interests in the global securities, except under the limited circumstances described below.

To facilitate subsequent transfers, all global securities deposited by direct participants with DTC will be registered in the name of DTC’s partnership nominee, Cede & Co., or such other name as may be requested by an authorized representative of DTC. The deposit of securities with DTC and their registration in the name of Cede & Co. or such other nominee will not change the beneficial ownership of the securities. DTC has no knowledge of the actual beneficial owners of the securities. DTC’s records reflect only the identity of the direct participants to whose accounts the securities are credited, which may or may not be the beneficial owners. The participants are responsible for keeping account of their holdings on behalf of their customers.

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So long as the securities are in book-entry form, you will receive payments and may transfer securities only through the facilities of the depositary and its direct and indirect participants. We will maintain an office or agency in the location specified in the prospectus supplement for the applicable securities, where notices and demands in respect of the securities and the indenture may be delivered to us and where certificated securities may be surrendered for payment, registration of transfer or exchange.

Conveyance of notices and other communications by DTC to direct participants, by direct participants to indirect participants and by direct participants and indirect participants to beneficial owners will be governed by arrangements among them, subject to any legal requirements in effect from time to time.

Redemption notices will be sent to DTC. If less than all of the securities of a particular series are being redeemed, DTC’s practice is to determine by lot the amount of the interest of each direct participant in the securities of such series to be redeemed.

Neither DTC nor Cede & Co. (or such other DTC nominee) will consent or vote with respect to the securities. Under its usual procedures, DTC will mail an omnibus proxy to us as soon as possible after the record date. The omnibus proxy assigns the consenting or voting rights of Cede & Co. to those direct participants to whose accounts the securities of such series are credited on the record date, identified in a listing attached to the omnibus proxy.

So long as securities are in book-entry form, we will make payments on those securities to the depositary or its nominee, as the registered owner of such securities, by wire transfer of immediately available funds. If securities are issued in definitive certificated form under the limited circumstances described below, we will have the option of making payments by check mailed to the addresses of the persons entitled to payment or by wire transfer to bank accounts in the United States designated in writing to the applicable trustee or other designated party at least 15 days before the applicable payment date by the persons entitled to payment, unless a shorter period is satisfactory to the applicable trustee or other designated party.

Redemption proceeds, distributions and dividend payments on the securities will be made to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC. DTC’s practice is to credit direct participants’ accounts upon DTC’s receipt of funds and corresponding detail information from us on the payment date in accordance with their respective holdings shown on DTC records. Payments by participants to beneficial owners will be governed by standing instructions and customary practices, as is the case with securities held for the account of customers in bearer form or registered in “street name.” Those payments will be the responsibility of participants and not of DTC or us, subject to any statutory or regulatory requirements in effect from time to time. Payment of redemption proceeds, distributions and dividend payments to Cede & Co., or such other nominee as may be requested by an authorized representative of DTC, is our responsibility; disbursement of payments to direct participants is the responsibility of DTC; and disbursement of payments to the beneficial owners is the responsibility of direct and indirect participants.

Except under the limited circumstances described below, purchasers of securities will not be entitled to have securities registered in their names and will not receive physical delivery of securities. Accordingly, each beneficial owner must rely on the procedures of DTC and its participants to exercise any rights under the securities and the indenture.

The laws of some jurisdictions may require that some purchasers of securities take physical delivery of securities in definitive form. Those laws may impair the ability to transfer or pledge beneficial interests in securities.

DTC may discontinue providing its services as securities depositary with respect to the securities at any time by giving reasonable notice to us. Under such circumstances, in the event that a successor depositary is not obtained, securities certificates are required to be printed and delivered.

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As noted above, beneficial owners of a particular series of securities generally will not receive certificates representing their ownership interests in those securities. However, if:

| • |  | DTC notifies us that it is unwilling or unable to continue as a depositary for the global security or securities representing such series of securities or if DTC ceases to be a clearing agency registered under the Exchange Act at a time when it is required to be registered and a successor depositary is not appointed within 90 days of the notification to us or of our becoming aware of DTC’s ceasing to be so registered, as the case may be;

| • |  | we determine, in our sole discretion, not to have such securities represented by one or more global securities; or

| • |  | an Event of Default has occurred and is continuing with respect to such series of securities,

then we will prepare and deliver certificates for such securities in exchange for beneficial interests in the global securities. Any beneficial interest in a global security that is exchangeable under the circumstances described in the preceding sentence will be exchangeable for securities in definitive certificated form registered in the names that the depositary directs. It is expected that these directions will be based upon directions received by the depositary from its participants with respect to ownership of beneficial interests in the global securities.

We have obtained the information in this section and elsewhere in this prospectus concerning DTC and DTC’s book-entry system from sources that are believed to be reliable, but we take no responsibility for the accuracy of this information.

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PLAN OF DISTRIBUTION

We may sell the securities from time to time pursuant to underwritten public offerings, negotiated transactions, block trades or a combination of these methods or through underwriters or dealers, through agents and/or directly to one or more purchasers. The securities may be distributed from time to time in one or more transactions:

| • |  | at a fixed price or prices, which may be changed;

| • |  | at market prices prevailing at the time of sale;

| • |  | at prices related to such prevailing market prices; or

| • |  | at negotiated prices.

Each time that we sell securities covered by this prospectus, we will provide a prospectus supplement or supplements that will describe the method of distribution and set forth the terms and conditions of the offering of such securities, including the offering price of the securities and the proceeds to us, if applicable.

Offers to purchase the securities being offered by this prospectus may be solicited directly. Agents may also be designated to solicit offers to purchase the securities from time to time. Any agent involved in the offer or sale of our securities will be identified in a prospectus supplement.

If a dealer is utilized in the sale of the securities being offered by this prospectus, the securities will be sold to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale.

If an underwriter is utilized in the sale of the securities being offered by this prospectus, an underwriting agreement will be executed with the underwriter at the time of sale and the name of any underwriter will be provided in the prospectus supplement that the underwriter will use to make resales of the securities to the public. In connection with the sale of the securities, we or the purchasers of securities for whom the underwriter may act as agent, may compensate the underwriter in the form of underwriting discounts or commissions. The underwriter may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/or commissions from the purchasers for which they may act as agent. Unless otherwise indicated in a prospectus supplement, an agent will be acting on a best efforts basis and a dealer will purchase securities as a principal, and may then resell the securities at varying prices to be determined by the dealer.

Any compensation paid to underwriters, dealers or agents in connection with the offering of the securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers will be provided in the applicable prospectus supplement. Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters within the meaning of the Securities Act of 1933, as amended, or the Securities Act, and any discounts and commissions received by them and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions. We may enter into agreements to indemnify underwriters, dealers and agents against civil liabilities, including liabilities under the Securities Act, or to contribute to payments they may be required to make in respect thereof and to reimburse those persons for certain expenses.

Any common stock will be listed on The Nasdaq Global Select Market, but any other securities may or may not be listed on a national securities exchange. To facilitate the offering of securities, certain persons participating in the offering may engage in transactions that stabilize, maintain or otherwise affect the price of the securities. This may include over-allotments or short sales of the securities, which involve the sale by persons participating in the offering of more securities than were sold to them. In these circumstances, these persons would cover such over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option, if any. In addition, these persons may stabilize or maintain the price of the securities by bidding for or

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purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

If indicated in the applicable prospectus supplement, underwriters or other persons acting as agents may be authorized to solicit offers by institutions or other suitable purchasers to purchase the securities at the public offering price set forth in the prospectus supplement, pursuant to delayed delivery contracts providing for payment and delivery on the date or dates stated in the prospectus supplement. These purchasers may include, among others, commercial and savings banks, insurance companies, pension funds, investment companies and educational and charitable institutions. Delayed delivery contracts will be subject to the condition that the purchase of the securities covered by the delayed delivery contracts will not at the time of delivery be prohibited under the laws of any jurisdiction in the United States to which the purchaser is subject. The underwriters and agents will not have any responsibility with respect to the validity or performance of these contracts.

We may engage in at the market offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement so indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be named in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus and an applicable prospectus supplement. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

The specific terms of any lock-up provisions in respect of any given offering will be described in the applicable prospectus supplement.

In compliance with the guidelines of the Financial Industry Regulatory Authority, Inc., or FINRA, the maximum consideration or discount to be received by any FINRA member or independent broker dealer may not exceed 8% of the aggregate proceeds of the offering.

The underwriters, dealers and agents may engage in transactions with us, or perform services for us, in the ordinary course of business for which they receive compensation.

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LEGAL MATTERS

Dentons Durham Jones Pinegar P.C., St. George, Utah, will pass upon certain legal matters relating to the issuance and sale of the securities offered hereby on behalf of Alphatec Holdings, Inc. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in the applicable prospectus supplement.

EXPERTS

The consolidated financial statements of Alphatec Holdings, Inc. as of December 31, 2022 and 2021, and for each of the two years in the period ended December 31, 2022, incorporated by reference in this Prospectus, and the effectiveness of Alphatec Holdings, Inc.’s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such consolidated financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

The consolidated statement of operations, comprehensive loss, stockholders’ equity and cash flows of Alphatec Holdings, Inc. as of December 31, 2020, and for the year ended December 31, 2020, incorporated by reference in this Prospectus to Alphatec Holdings, Inc.’s annual report on Form 10-K for the year ended December 31, 2022, have been audited by Mayer Hoffman McCann P.C., an independent registered public accounting firm, as stated in their reports. Such consolidated financial statements are incorporated by reference in reliance upon the reports of such firm given their authority as experts in accounting and auditing.

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4,285,715 Shares

Common Stock

Sole Book-Running Manager

TD Cowen

April 19, 2023