DEF 14A 1 ny20002411x1_def14a.htm FORM DEF 14A

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549
SCHEDULE 14A
(Rule 14a-101)
INFORMATION REQUIRED IN PROXY STATEMENT
SCHEDULE 14A INFORMATION
Proxy Statement Pursuant to Section 14(a) of
the Securities Exchange Act of 1934 (Amendment No.   )

Filed by the Registrant ☒ | ​ | ​ | Filed by a Party other than the Registrant ☐

Check the appropriate box:
☐ | ​ | ​ | Preliminary Proxy Statement
☐ | ​ | ​ | Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
☒ | ​ | ​ | Definitive Proxy Statement
☐ | ​ | ​ | Definitive Additional Materials
☐ | ​ | ​ | Soliciting Material under §240.14a-12

Rapid Micro Biosystems, Inc.
(Name of Registrant as Specified in its Charter)
(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

Payment of Filing Fee (Check all boxes that apply):
☒ | ​ | ​ | No fee required.
☐ | ​ | ​ | Fee paid previously with preliminary materials.
☐ | ​ | ​ | Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

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Rapid Micro Biosystems, Inc.
NOTICE & PROXY
STATEMENT
Annual Meeting of Stockholders
May 23, 2022
4:00 p.m. (Eastern Time)

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RAPID MICRO BIOSYSTEMS, INC.
1001 PAWTUCKET BOULEVARD WEST, SUITE 280
LOWELL, MASSACHUSETTS 01854
April 8, 2022
Dear Fellow Stockholders:
You are cordially invited to attend the 2022 Annual Meeting of Stockholders (the “Annual Meeting”) of Rapid Micro Biosystems, Inc. (the “Company”) which will be conducted virtually on Monday, May 23, 2022, beginning at 4:00 PM, Eastern Time. Our Annual Meeting will be a completely virtual meeting of stockholders, which will be conducted via live webcast. You will be able to attend the virtual Annual Meeting, vote your shares electronically and submit your questions during the meeting by visiting www.virtualshareholdermeeting.com/RPID2022. Utilizing the latest technology and a virtual meeting format will allow stockholders to participate from any location and we expect will lead to increased attendance, improved communications, lowered environmental impacts from travel and cost savings for our stockholders and the Company.
The Notice of Meeting and Proxy Statement on the following pages describe the matters to be presented at the Annual Meeting. Details regarding how to attend the meeting and the business to be conducted at the Annual Meeting are more fully described in the Notice of Annual Meeting and Proxy Statement.
Whether or not you attend the Annual Meeting, it is important that your shares be represented and voted at the Annual Meeting. We are providing proxy material access to our stockholders via the Internet at www.proxyvote.com. Internet distribution of our proxy materials conserves natural resources, lowers the cost of the Annual Meeting, and expedites receipt by stockholders. The matters to be acted upon at the Annual Meeting are also described in the Notice of Internet Availability of Proxy Materials, or Notice of Internet Availability, that you will receive in the mail. Please give the proxy materials your careful attention.
You may vote via the Internet or by telephone by following the instructions on your Notice of Internet Availability. In order to vote via the Internet or by telephone, you must have the stockholder identification number provided in your Notice of Internet Availability. If you requested a proxy card by mail, you may vote by voting, signing and returning the proxy card in the postage-paid envelope provided. If you attend the Annual Meeting online, you may electronically vote at the meeting even if you previously returned your proxy card or voted via the Internet or by telephone. Please review the instructions for each voting option described in the Notice of Internet Availability and in the Proxy Statement.
Your vote is very important to us and to our business. Prior to the meeting, we encourage all of our stockholders to review these proxy materials and vote your shares.
Thank you for your support.
Sincerely,
Robert Spignesi
President and Chief Executive Officer
Jeffrey Schwartz
Chairperson of the Board of Directors

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Notice of Annual Meeting of Stockholders
To be Held on Monday, May 23, 2022
RAPID MICRO BIOSYSTEMS, INC.
1001 PAWTUCKET BOULEVARD WEST, SUITE 280, LOWELL, MASSACHUSETTS 01854
The 2022 Annual Meeting of Stockholders (the “Annual Meeting”) of Rapid Micro Biosystems, Inc., a Delaware corporation (the “Company”), will be held at 4:00 p.m., Eastern Time, on Monday, May 23, 2022. The Annual Meeting will be a completely virtual meeting, which will be conducted via live webcast. You will be able to attend the Annual Meeting electronically and submit your questions during the meeting by visiting www.virtualshareholdermeeting.com/RPID2022. The Annual Meeting is called for the following purposes:

(1) | To elect David Hirsch and Inese Lowenstein as Class I Directors to serve until the 2025 Annual Meeting of Stockholders and until their respective successors shall have been duly elected and qualified, or until their earlier death, resignation or removal;

(2) | To ratify the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2022; and

(3) | To transact such other business as may properly come before the Annual Meeting or any continuation, postponement, or adjournment of the Annual Meeting.

Only holders of record of our outstanding shares of Class A common stock at the close of business on March 31, 2022, are entitled to notice of and to vote at the Annual Meeting, or any continuation, postponement or adjournment of the Annual Meeting. The Annual Meeting may be continued or adjourned from time to time without notice other than by announcement at the Annual Meeting. The holders of our Class B common stock are not entitled to notice of, or to vote on, any matter before the Annual Meeting.
Important information for holders of Class A common stock:
We are providing proxy material access to our stockholders via the Internet at www.proxyvote.com. The matters to be acted upon at the Annual Meeting are described in the Notice of Internet Availability of Proxy Materials that you receive in the mail. Please give the proxy materials your careful attention.
In addition to their availability at www.proxyvote.com, this proxy statement and our 2021 annual report to stockholders are available for viewing, printing and downloading at investors.rapidmicrobio.com.
It is important that your shares be represented regardless of the number of shares you may hold. Whether or not you plan to attend the Annual Meeting we urge you to vote your shares via the toll-free telephone number or over the Internet, as described in the enclosed materials. If you received a copy of the proxy card by mail, you may sign, date and mail the proxy card in the enclosed return envelope. Promptly voting your shares will ensure the presence of a quorum at the Annual Meeting and will save us the expense of further solicitation. Submitting your proxy now will not prevent you from voting your shares at the Annual Meeting if you desire to do so, as your proxy is revocable at your option.
By Order of the Board of Directors
Jonathan Paris
SVP, Secretary and General Counsel
Lowell, Massachusetts
April 8, 2022
Your vote is important. Please vote.

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| ​ | ​ | Page
PROXY STATEMENT | ​ | ​ | 1
PROPOSALS | ​ | ​ | 3
RECOMMENDATIONS OF THE BOARD | ​ | ​ | 3
INFORMATION ABOUT THIS PROXY STATEMENT | ​ | ​ | 3
QUESTIONS AND ANSWERS ABOUT THE 2022 ANNUAL MEETING OF STOCKHOLDERS | ​ | ​ | 4
PART 1 - PROPOSALS TO BE VOTED ON AT THE MEETING | ​ | ​ | 10
PROPOSAL 1: Election of Directors | ​ | ​ | 10
PROPOSAL 2: Ratification of Appointment of Independent Registered Public Accounting Firm | ​ | ​ | 12
PART 2 - CORPORATE GOVERNANCE | ​ | ​ | 13
GENERAL | ​ | ​ | 13
BOARD COMPOSITION | ​ | ​ | 13
DIRECTOR INDEPENDENCE | ​ | ​ | 13
EXECUTIVE SESSIONS | ​ | ​ | 13
DIRECTOR CANDIDATES | ​ | ​ | 13
COMMUNICATIONS FROM INTERESTED PARTIES | ​ | ​ | 14
BOARD LEADERSHIP STRUCTURE AND ROLE IN RISK OVERSIGHT | ​ | ​ | 14
ANTI-HEDGING POLICY | ​ | ​ | 15
CODE OF ETHICS | ​ | ​ | 15
PART 3 – BOARD OF DIRECTORS | ​ | ​ | 16
BOARD DIVERSITY MATRIX | ​ | ​ | 19
ATTENDANCE BY MEMBERS OF THE BOARD OF DIRECTORS AT MEETINGS | ​ | ​ | 19
COMMITTEES OF THE BOARD | ​ | ​ | 20
AUDIT COMMITTEE | ​ | ​ | 20
COMPENSATION COMMITTEE | ​ | ​ | 21
NOMINATING AND CORPORATE GOVERNANCE COMMITTEE | ​ | ​ | 21
DIRECTOR COMPENSATION | ​ | ​ | 22
2021 DIRECTOR COMPENSATION TABLE | ​ | ​ | 22
NON-EMPLOYEE DIRECTOR COMPENSATION PROGRAM | ​ | ​ | 24
PART 4 - EXECUTIVE OFFICERS | ​ | ​ | 25
EXECUTIVE COMPENSATION | ​ | ​ | 26
NARRATIVE DISCLOSURE TO SUMMARY COMPENSATION TABLE | ​ | ​ | 27
EQUITY COMPENSATION PLAN INFORMATION | ​ | ​ | 32
PART 5 - AUDIT COMMITTEE MATTERS | ​ | ​ | 33
REPORT OF THE AUDIT COMMITTEE OF THE BOARD OF DIRECTORS | ​ | ​ | 33
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FEES AND OTHER MATTERS | ​ | ​ | 34
POLICY ON AUDIT COMMITTEE PRE-APPROVAL OF AUDIT AND PERMISSIBLE NON-AUDIT SERVICES OF INDEPENDENT AUDITOR | ​ | ​ | 34
PART 6 - SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT | ​ | ​ | 35
CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS | ​ | ​ | 38
POLICIES AND PROCEDURES FOR RELATED PERSON TRANSACTIONS | ​ | ​ | 40
PART 7 - OTHER MATTERS | ​ | ​ | 41
COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION | ​ | ​ | 41
STOCKHOLDERS’ PROPOSALS | ​ | ​ | 41
OTHER MATTERS AT THE ANNUAL MEETING | ​ | ​ | 41
SOLICITATION OF PROXIES | ​ | ​ | 41
RAPID MICRO BIOSYSTEMS’ ANNUAL REPORT ON FORM 10-K | ​ | ​ | 42

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PROXY STATEMENT
RAPID MICRO BIOSYSTEMS, INC.
1001 PAWTUCKET BOULEVARD WEST, SUITE 280, LOWELL, MASSACHUSETTS 01854
This proxy statement is furnished in connection with the solicitation by the Board of Directors (the “Board of Directors” or “Board”) of Rapid Micro Biosystems, Inc. of proxies to be voted at our Annual Meeting of Stockholders to be held on Monday, May 23, 2022 (the “Annual Meeting” or “2022 Annual Meeting”), at 4:00 p.m., Eastern Time, and at any continuation, postponement, or adjournment of the Annual Meeting. The Annual Meeting will be a completely virtual meeting, which will be conducted via live webcast. You will be able to attend the Annual Meeting and submit your questions during the meeting by visiting www.virtualshareholdermeeting.com/RPID2022 and entering your 16-digit control number included in your Notice of Internet Availability of Proxy Materials, on your proxy card or on the instructions that accompanied your proxy materials.
Only holders of record of outstanding shares of our Class A common stock (our “Class A stockholders”) at the close of business on March 31, 2022 (the “Record Date”) will be entitled to notice of, and to vote at, the Annual Meeting and any continuation, postponement, or adjournment of the Annual Meeting. Each share of our Class A common stock entitles its holder to one vote per share on all matters presented to our stockholders. At the close of business on the Record Date, there were 36,386,948 shares of Class A common stock outstanding and entitled to vote at the Annual Meeting. The holders of our Class B common stock are not entitled to notice of or to vote on any matter before the Annual Meeting.
Even if you plan to attend the Annual Meeting online, we encourage you to vote in advance of the Annual Meeting as described in this proxy statements, so that your vote will be counted if you later decide not to attend the Annual Meeting or encounter technical difficulties. If you wish to submit your votes before the virtual Annual Meeting, then you do not have to vote at the Annual Meeting unless you wish to change your vote.
If you do not have a 16-digit control number, you may still attend the Annual Meeting as a guest in listen-only mode. To attend as a guest, please visit www.virtualshareholdermeeting.com/RPID2022 and enter the information requested on the screen to register as a guest. Please note that you will not have the ability to vote or ask questions during the meeting if you participate as a guest.
This proxy statement, form of proxy and the Company’s 2021 Annual Report to Stockholders for the fiscal year ended December 31, 2021 (the “2021 Annual Report”) will be released on or about April 8, 2022 to our Class A stockholders as of the Record Date.
In this proxy statement, “we,” “us,” “our,” the “Company” and “Rapid Micro Biosystems” refer to Rapid Micro Biosystems, Inc., and, unless otherwise stated, all of its subsidiaries.
This proxy statement, the accompanying proxy card and our 2021 Annual Report to stockholders were first made available to stockholders on or about April 8, 2022.
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IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS
FOR THE ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON MONDAY, MAY 23, 2022
This Proxy Statement and our 2021 Annual Report to Stockholders,
which includes our Annual Report on Form 10-K for the fiscal year ended December 31, 2021,
are available at http://www.proxyvote.com/
and at investors.rapidmicrobio.com under the tab “Financial Information”
for viewing, downloading and printing.
A copy of our Annual Report on Form 10-K for the year ended December 31, 2021 as filed with the Securities and Exchange Commission, or SEC, except for exhibits, will be furnished without charge to any stockholder upon written or oral request to Rapid Micro Biosystems, Inc., 1001 Pawtucket Boulevard West, Suite 280, Lowell, MA 01854, Attention: Investor Relations, Telephone 1-978-349-3200.
To attend, vote and submit questions during the Annual Meeting visit www.virtualshareholdermeeting.com/RPID2022 and enter the control number included in your Notice of Internet Availability of Proxy Materials, voting instruction form, or proxy card. Stockholders may vote during the Annual Meeting by following the instructions available on the Annual Meeting Website. Those without a control number may attend as guests of the meeting, but will not have the option to vote or ask questions during the virtual meeting. Online access to the webcast will open approximately 15 minutes prior to the start of the Annual Meeting. To submit questions in advance of the Annual Meeting, visit www.proxyvote.com before noon Eastern Time on May 22, 2022 and enter your control number.
All stockholders—even if you plan on attending the Annual Meeting—are encouraged to vote their shares in advance online or, if you requested printed copies of the proxy materials, by phone or by mail, to ensure that your vote will be represented at the Annual Meeting. For more detailed information, see the section entitled “How Do I Vote” beginning on page 5 of this Proxy Statement.
Proxy Materials Are Available on the Internet
Rapid Micro Biosystems uses the Internet as the primary means of furnishing proxy materials to stockholders. We send a Notice of Internet Availability of Proxy Materials (the “Notice of Internet Availability”) to our stockholders with instructions on how to access the proxy materials online at proxyvote.com or request a printed copy of materials.
Stockholders may follow the instructions in the Notice of Internet Availability to elect to receive future proxy materials in print by mail or electronically by email. We encourage stockholders to take advantage of the availability of proxy materials online to reduce environmental impact and mailing costs.
Rapid Micro Biosystems’ proxy materials are also available at investors.rapidmicrobio.com.
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PROPOSALS
At the Annual Meeting, our stockholders will be asked:

(1) | To elect David Hirsch and Inese Lowenstein as Class I Directors to serve until the 2025 Annual Meeting of Stockholders and until their respective successors shall have been duly elected and qualified, or until their earlier death, resignation or removal;

(2) | To ratify the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2022; and

(3) | To transact such other business as may properly come before the Annual Meeting or any continuation, postponement, or adjournment of the Annual Meeting.

We know of no other business that will be presented at the Annual Meeting. If any other matter properly comes before the stockholders for a vote at the Annual Meeting, however, the proxy holders named on the Company’s proxy card will vote your shares in accordance with their best judgment.
RECOMMENDATIONS OF THE BOARD
The Board recommends that you vote your shares as indicated below. If you return a properly completed proxy card, or vote your shares by telephone or Internet, your shares of Class A common stock will be voted on your behalf as you direct. If not otherwise specified, the shares of Class A common stock represented by the proxies will be voted, and the Board recommends that you vote:

(1) | FOR the election of David Hirsch and Inese Lowenstein as Class I Directors to serve until the 2025 Annual Meeting of Stockholders and until their respective successors shall have been duly elected and qualified, or until their earlier death, resignation or removal; and

(2) | FOR the ratification of the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2022.

INFORMATION ABOUT THIS PROXY STATEMENT
Why you received this proxy statement. You are viewing or have received these proxy materials because Rapid Micro Biosystems’ Board is soliciting your proxy to vote your shares at the Annual Meeting. This proxy statement includes information that we are required to provide to you under the rules of the Securities and Exchange Commission (the “SEC”) and that are designed to assist you in voting your shares.
Notice of Internet Availability of Proxy Materials. As permitted by SEC rules, Rapid Micro Biosystems is making this proxy statement and its 2021 Annual Report available to its Class A stockholders electronically via the Internet. On or about April 8, 2022, we mailed to our Class A stockholders a Notice of Internet Availability of Proxy Materials (the “Notice of Internet Availability”) containing instructions on how to access this proxy statement and our 2021 Annual Report and vote online. If you received a Notice of Internet Availability by mail, you will not receive a printed copy of the proxy materials in the mail unless you specifically request them. Instead, the Notice of Internet Availability instructs you on how to access and review all of the important information contained in this proxy statement and 2021 Annual Report. The Notice of Internet Availability also instructs you on how you may submit your proxy over the Internet. If you received a Notice of Internet Availability by mail and would like to receive a printed copy of our proxy materials, you should follow the instructions for requesting such materials contained in the Notice of Internet Availability.
Printed Copies of Our Proxy Materials. If you received printed copies of our proxy materials, then instructions regarding how you can vote are contained on the proxy card included in the materials.
Householding. The SEC’s rules permit us to deliver a single set of proxy materials to one address shared by two or more of our stockholders. This delivery method is referred to as “householding” and can result in significant cost savings. To take advantage of this opportunity, we have delivered only one set of proxy materials to multiple stockholders who share an address, unless we received contrary instructions from the impacted stockholders prior to the mailing date. We agree to deliver promptly, upon written or oral request, a separate set of proxy materials, as requested, to any stockholder at the shared address to which a single set of those documents was delivered. If you prefer to receive separate copies of the proxy materials for the Annual Meeting or in the future, contact Broadridge Financial Solutions, Inc. at 1-866-540-7095 or in writing at Broadridge, Householding Department, 51 Mercedes Way, Edgewood, New York 11717.
If you are currently a stockholder sharing an address with another stockholder and wish to receive only one set of future proxy materials for your household, please contact Broadridge at the above phone number or address.
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QUESTIONS AND ANSWERS ABOUT THE 2022 ANNUAL MEETING OF STOCKHOLDERS
WHO IS ENTITLED TO VOTE AT THE ANNUAL MEETING?
The Record Date for the Annual Meeting is March 31, 2022. You are entitled to vote at the Annual Meeting only if you were a Class A stockholder of record at the close of business on that date, or if you hold a valid proxy for the Annual Meeting. You will need to obtain your own Internet access if you choose to attend the Annual Meeting and/or vote over the Internet. Each share of our Class A common stock entitles its holder to one vote per share on all matters presented to our stockholders. The holders of our Class B common stock are not entitled to vote on any matter before the Annual Meeting. If the holders of our Class B common stock convert their shares to Class A common stock after the Record Date, such Class A common stock will not be entitled to vote at the Annual Meeting. At the close of business on the Record Date, there were 36,386,948 shares of Class A common stock issued and outstanding and entitled to vote at the Annual Meeting.
WHAT IS THE DIFFERENCE BETWEEN BEING A “RECORD HOLDER” AND HOLDING SHARES IN “STREET NAME”?
A record holder holds shares in his or her name. Shares held in “street name” means shares that are held in the name of a bank or broker on a person’s behalf.
AM I ENTITLED TO VOTE IF MY SHARES ARE HELD IN “STREET NAME”?
Yes. If your shares are held by a bank or a brokerage firm, you are considered the “beneficial owner” of those shares held in “street name.” If your shares are held in street name, our proxy materials are being provided to you by your bank or brokerage firm, along with a voting instruction card if you received printed copies of our proxy materials. As the beneficial owner, you have the right to direct your bank or brokerage firm how to vote your shares, and the bank or brokerage firm is required to vote your shares in accordance with your instructions. If you haven’t received a 16-digit control number, you should contact your bank or broker to obtain your control number or otherwise vote through the bank or broker.
HOW MANY SHARES MUST BE PRESENT TO HOLD THE ANNUAL MEETING?
A quorum must be present at the Annual Meeting for any business to be conducted. The presence at the Annual Meeting, electronically or by proxy, of the holders of a majority in voting power of Class A common stock issued and outstanding and entitled to vote on the Record Date will constitute a quorum.
WHO CAN ATTEND THE 2022 ANNUAL MEETING OF STOCKHOLDERS?
You may attend the Annual Meeting only if you are a Rapid Micro Biosystems stockholder who is entitled to vote at the Annual Meeting, or if you hold a valid proxy for the Annual Meeting. The Annual Meeting will be held entirely online to allow greater participation. You will be able to attend the Annual Meeting and submit your questions by visiting the following website: www.virtualshareholdermeeting.com/RPID2022. You will also be able to vote your shares electronically at the Annual Meeting.
To participate in the Annual Meeting, you will need the 16-digit control number included in your Notice of Internet Availability, on your proxy card or on the instructions that accompanied your proxy materials. If you hold your shares through a bank or broker, instructions should also be provided on the voting instruction card provided by your bank or brokerage firm. You will need to obtain your own Internet access if you choose to attend the Annual Meeting online and/or vote over the Internet. If you lose your 16-digit control number, you may join the Annual Meeting as a “Guest,” but you will not be able to vote, ask questions, or access the list of stockholders as of the Record Date.
The meeting webcast will begin promptly at 4:00 p.m., Eastern Time. We encourage you to access the meeting prior to the start time. Online check-in will begin at 3:45 p.m., Eastern Time, and you should allow ample time for check-in procedures.
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WHY A VIRTUAL MEETING?
We are excited to embrace the latest technology to provide expanded access, improved communication and cost savings for us and our stockholders. We believe the virtual meeting will enable increased stockholder attendance and participation since stockholders can participate from any location around the world. Furthermore, as part of our effort to maintain a safe and healthy environment for our directors, members of management and stockholders who wish to attend the Annual Meeting, in light of the COVID-19 pandemic, we believe that hosting a virtual meeting is in the best interests of the Company and such attendees of the Annual Meeting.
WHAT IF DURING THE CHECK-IN TIME OR DURING THE ANNUAL MEETING I HAVE TECHNICAL DIFFICULTIES OR TROUBLE ACCESSING THE VIRTUAL MEETING WEBSITE?
We will have technicians ready to assist you with any technical difficulties you may have accessing the virtual meeting website and information for assistance will be located on the Annual Meeting login page. If you experience technical difficulties during the check-in process or during the meeting, a technical assistance phone number will be made available on the virtual meeting registration page 15 minutes prior to the start time of the meeting.
WHAT IF A QUORUM IS NOT PRESENT AT THE ANNUAL MEETING?
If a quorum is not present at the scheduled time of the Annual Meeting, (i) the chairperson of the Annual Meeting or (ii) a majority in voting power of the stockholders entitled to vote at the Annual Meeting, present electronically or represented by proxy, may adjourn the Annual Meeting until a quorum is present or represented.
WHAT DOES IT MEAN IF I RECEIVE MORE THAN ONE NOTICE OF INTERNET AVAILABILITY OR MORE THAN ONE SET OF PROXY MATERIALS?
It means that your shares are held in more than one account at the transfer agent and/or with banks or brokers. Please vote all of your shares. To ensure that all of your shares are voted, for each Notice of Internet Availability or set of proxy materials, please submit your proxy by phone, via the Internet, or, if you received printed copies of the proxy materials, by signing, dating and returning the enclosed proxy card in the enclosed envelope.
HOW DO I VOTE?
We recommend that stockholders vote by proxy even if they plan to participate in the Annual Meeting and vote electronically during the meeting. If you are a stockholder of record, there are three ways to vote by proxy:

• | by Internet—You can vote over the Internet at www.proxyvote.com by following the instructions on the Notice of Internet Availability or proxy card;

• | by Telephone—You can vote by telephone by calling 1-800-690-6903 and following the instructions on the proxy card;

• | by Mail—You can vote by mail by signing, dating and mailing the proxy card, which you may have received by mail; or

• | Online during the Annual Meeting—You can vote online during the Annual Meeting by visiting www.virtualshareholdermeeting.com/RPID2022 and entering the 16-digit control number included on your Notice of Internet Availability, proxy card or the instructions that accompanied your proxy materials, and following the on-screen instructions. The availability of online voting may depend on the voting procedures of the organization that holds your shares. The meeting webcast will begin promptly at 4:00 p.m. Eastern Time. Online access will open approximately 15 minutes prior to the start of the Annual Meeting to allow time for you to log in and test your system. If you experience technical difficulties during the check-in process or during the meeting, a technical assistance phone number will be made available on the virtual meeting registration page 15 minutes prior to the start time of the meeting.

Internet and telephone voting facilities for stockholders of record will be available 24 hours a day and will close at 11:59 p.m., Eastern Time, on May 22, 2022. Stockholders may vote at the Annual Meeting by visiting www.virtualshareholdermeeting.com/RPID2022 and entering the 16-digit control number included on your Notice
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of Internet Availability, proxy card or the instructions that accompanied your proxy materials. The Annual Meeting webcast will begin promptly at 4:00 p.m., Eastern Time, on Monday, May 23, 2022. In light of possible disruptions or delays in mail service related to the COVID-19 pandemic, we encourage stockholders to submit their proxy via telephone or the Internet.
If your shares are held in street name through a bank or broker, you will receive instructions on how to vote from the bank or broker. You must follow their instructions in order for your shares to be voted. Internet and telephone voting also may be offered to stockholders owning shares through certain banks and brokers. If your shares are not registered in your own name and you would like to vote your shares at the Annual Meeting, you may visit www.virtualshareholdermeeting.com/RPID2022 and enter the 16-digit control number included in the voting instruction card provided to you by your bank or brokerage firm. If you hold your shares in street name and you do not receive a 16-digit control number, you may need to log in to your bank or brokerage firm’s website and select the shareholder communications mailbox to access the meeting and vote. Instructions should also be provided on the voting instruction card provided by your bank or brokerage firm.
CAN I CHANGE MY VOTE AFTER I SUBMIT MY PROXY?
Yes.
If you are a registered stockholder, you may revoke your proxy and change your vote:

• | by submitting a duly executed proxy bearing a later date;

• | by granting a subsequent proxy through the Internet or telephone;

• | by giving written notice of revocation to the Secretary of Rapid Micro Biosystems prior to the Annual Meeting; or

• | by voting electronically at the Annual Meeting.

Your most recent proxy card or Internet or telephone proxy is the one that is counted. Your virtual attendance at the Annual Meeting by itself will not revoke your proxy unless you give written notice of revocation to the Secretary before your proxy is voted or you vote electronically during the Annual Meeting.
If your shares are held in street name, you may change or revoke your voting instructions by following the specific directions provided to you by your bank or broker, or you may vote electronically during the Annual Meeting.
WHO WILL COUNT THE VOTES?
A representative of Broadridge Financial Solutions, Inc., our inspector of election, will tabulate and certify the votes.
WHAT IF I DO NOT SPECIFY HOW MY SHARES ARE TO BE VOTED?
If you submit a proxy but do not indicate any voting instructions, the persons named as proxies will vote in accordance with the recommendations of the Board. The Board’s recommendations are indicated on page 3 of this proxy statement, as well as with the description of each proposal in this proxy statement.
WILL ANY OTHER BUSINESS BE CONDUCTED AT THE ANNUAL MEETING?
We know of no other business that will be presented at the Annual Meeting. If any other matter properly comes before the stockholders for a vote at the Annual Meeting, however, the proxy holders named on the Company’s proxy card will vote your shares in accordance with their best judgment.
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HOW MANY VOTES ARE REQUIRED FOR THE APPROVAL OF THE PROPOSALS TO BE VOTED UPON AND HOW WILL ABSTENTIONS AND BROKER NON-VOTES BE TREATED?

Proposal | ​ | ​ | Votes Required | ​ | ​ | Effect of Votes Withheld / Abstentions and Broker Non-Votes
Proposal 1: Election of Directors | ​ | ​ | The plurality of the votes cast. This means that the two nominees receiving the highest number of affirmative “FOR” votes will be elected as Class I Directors. | ​ | ​ | Votes withheld and broker non-votes will have no effect.
| ​ | ​ |  | ​ | ​ |
Proposal 2: Ratification of Appointment of Independent Registered Public Accounting Firm | ​ | ​ | The affirmative vote of the holders of a majority in voting power of the votes cast affirmatively or negatively by the holders entitled to vote on the proposal. | ​ | ​ | Abstentions will have no effect. We do not expect any broker non-votes on this proposal.

WHAT IS AN ABSTENTION AND HOW WILL VOTES WITHHELD AND ABSTENTIONS BE TREATED?
A “vote withheld,” in the case of the proposal regarding the election of directors, or an “abstention,” in the case of the proposal regarding the ratification of the appointment of PricewaterhouseCoopers LLP, represents a stockholder’s affirmative choice to decline to vote on a proposal. Votes withheld and abstentions are counted as present and entitled to vote for purposes of determining a quorum. Votes withheld have no effect on the election of directors. Abstentions have no effect on the ratification of the appointment of PricewaterhouseCoopers LLP.
WHAT ARE BROKER NON-VOTES AND DO THEY COUNT FOR DETERMINING A QUORUM?
Generally, broker non-votes occur when shares held by a broker in “street name” for a beneficial owner are not voted with respect to a particular proposal because the broker (1) has not received voting instructions from the beneficial owner and (2) lacks discretionary voting power to vote those shares. A broker is entitled to vote shares held for a beneficial owner on routine matters, such as the ratification of the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm, without instructions from the beneficial owner of those shares. On the other hand, absent instructions from the beneficial owner of such shares, a broker is not entitled to vote shares held for a beneficial owner on non-routine matters, such as the election of directors. Broker non-votes count for purposes of determining whether a quorum is present.
WHERE CAN I FIND THE VOTING RESULTS OF THE 2022 ANNUAL MEETING OF STOCKHOLDERS?
We plan to announce preliminary voting results at the Annual Meeting and we will report the final results in a Current Report on Form 8-K, which we intend to file with the SEC shortly after the Annual Meeting.
WILL THERE BE A QUESTION AND ANSWER SESSION DURING THE ANNUAL MEETING?
As part of the Annual Meeting, we will hold a live Q&A session, during which we intend to answer appropriate questions submitted by stockholders prior to and during the meeting that are pertinent to the Company and the meeting matters, after the completion of the Annual Meeting. Only stockholders that have accessed the Annual Meeting as a stockholder (rather than a “Guest”) by following the procedures outlined above in “Who can attend the 2022 Annual Meeting of Stockholders?” will be permitted to submit questions prior to and during the Annual Meeting. Each stockholder is limited to no more than two questions. Questions should be succinct and only cover a single topic. We will not address questions that are, among other things:

• | irrelevant to the business of the Company or to the business of the Annual Meeting;

• | related to material non-public information of the Company, including the status or results of our business since our last Quarterly Report on Form 10-Q;

• | related to any pending, threatened or ongoing litigation;

• | related to personal grievances;

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• | derogatory references to individuals or that are otherwise in bad taste;

• | substantially repetitious of questions already made by another stockholder;

• | in excess of the two question limit;

• | in furtherance of the stockholder’s personal or business interests; or

• | out of order or not otherwise suitable for the conduct of the Annual Meeting as determined by the Chairperson or Secretary in their reasonable judgment.

Additional information regarding the Q&A session will be available in the “Rules of Conduct” available on the Annual Meeting webpage for stockholders that have accessed the Annual Meeting as a stockholder (rather than a “Guest”) by following the procedures outlined above in “Who can attend the 2022 Annual Meeting of Stockholders?”.
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This proxy statement, the accompanying proxy card and our 2021 Annual Report to stockholders were first made available to stockholders on or about April 8, 2022.
IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS
FOR THE ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON MONDAY, MAY 23, 2022
This Proxy Statement and our 2021 Annual Report to Stockholders,
which includes our Annual Report on Form 10-K for the fiscal year ended December 31, 2021,
are available at http://www.proxyvote.com/
and at investors.rapidmicrobio.com under the tab “Financial Information”
for viewing, downloading and printing.
A copy of our Annual Report on Form 10-K for the year ended December 31, 2021 as filed with the Securities and Exchange Commission, or SEC, except for exhibits, will be furnished without charge to any stockholder upon written or oral request to Rapid Micro Biosystems, Inc., 1001 Pawtucket Boulevard West, Suite 280, Lowell, MA 01854, Attention: Investor Relations, Telephone 1-978-349-3200.
Proxy Materials Are Available on the Internet
Rapid Micro Biosystems uses the Internet as the primary means of furnishing proxy materials to stockholders. We send a Notice of Internet Availability of Proxy Materials (the “Notice of Internet Availability”) to our stockholders with instructions on how to access the proxy materials online at proxyvote.com or request a printed copy of materials.
Stockholders may follow the instructions in the Notice of Internet Availability to elect to receive future proxy materials in print by mail or electronically by email. We encourage stockholders to take advantage of the availability of proxy materials online to reduce environmental impact and mailing costs.
Rapid Micro Biosystems’ proxy materials are also available at investors.rapidmicrobio.com.
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PART 1 - PROPOSALS TO BE VOTED ON
PROPOSAL 1: Election of Directors
At the Annual Meeting, two (2) Class I Directors are to be elected to hold office until the 2025 Annual Meeting of Stockholders and until such director’s successor is elected and qualified or until such director’s earlier death, resignation or removal.
In accordance with the terms of our restated certificate of incorporation and amended and restated bylaws, our Board is currently divided into three classes with staggered, three-year terms. At each annual meeting of stockholders, the successor to each director whose term then expires will be elected to serve from the time of election and qualification until the third annual meeting of stockholders following election or such director’s death, resignation or removal, whichever is earliest to occur. The current class structure is as follows: Class I, whose term currently expires at the 2022 Annual Meeting of Stockholders and whose subsequent term will expire at the 2025 Annual Meeting of Stockholders; Class II, whose term will expire at the 2023 Annual Meeting of Stockholders; and Class III, whose term will expire at the 2024 Annual Meeting of Stockholders.
David Hirsch and Inese Lowenstein are current Class I Directors whose terms expire at the Annual Meeting. The Board, upon the recommendation of our Nominating and Corporate Governance Committee, has nominated Dr. Hirsch and Ms. Lowenstein for election as Class I Directors, each to hold office until the 2025 Annual Meeting of Stockholders and until their successor has been duly elected and qualified or until their earlier death, resignation or removal.
The two nominees receiving the highest number of affirmative “FOR” votes will be elected as Class I Directors. This is called plurality. Votes withheld and broker non-votes will have no effect on the outcome of the vote on this proposal.
If you submit a proxy but do not indicate any voting instructions, the persons named as proxies will vote the shares of Class A common stock represented by the proxy for the election as Class I Directors the persons whose names and biographies appear below. All of the persons whose names and biographies appear below are currently serving as our directors. In the event any of the nominees should become unable to serve or for good cause will not serve as a director, it is intended that votes will be cast for a substitute nominee designated by the Board or the Board may elect to reduce its size. The Board has no reason to believe that the nominees named below will be unable to serve if elected. Each of the nominees has consented to being named in this proxy statement and to serve if elected.
NOMINEES FOR CLASS I DIRECTORS (CURRENT TERMS TO EXPIRE AT THE 2022 ANNUAL MEETING)
The nominees for election to the Board as Class I Directors are as follows:

Name | ​ | ​ | Age | ​ | ​ | Served as a Director Since | ​ | ​ | Positions with Rapid Micro Biosystems
David Hirsch, M.D., Ph.D. | ​ | ​ | 51 | ​ | ​ | 2013 | ​ | ​ | Director
Inese Lowenstein | ​ | ​ | 49 | ​ | ​ | 2021 | ​ | ​ | Director

The principal occupations and business experience, for at least the past five years, of each Class I Director nominee are as follows, as of April 8, 2022:

DAVID HIRSCH, M.D., Ph.D. | ​ | ​ | Age 51

David Hirsch, M.D., Ph.D. has served as a member of our Board since June 2013. Dr. Hirsch has served as a Managing Director of Longitude Capital Management Co., LLC, a venture capital firm that Dr. Hirsch co-founded, in July 2006, where he focuses on investments in biotechnology. Dr. Hirsch has served on the board of directors of Poseida Therapeutics, Inc. since March 2018, Molecular Templates, Inc. since August 2017, and Tricida, Inc. since June 2013. Dr. Hirsch previously served on the board of directors of Collegium Pharmaceutical from January 2012 to July 2020. Dr. Hirsch holds a Ph.D. in Biology from the Massachusetts Institute of Technology, an M.D. from Harvard Medical School and a B.A. in Biology from Johns Hopkins University. We believe that Dr. Hirsch’s extensive experience serving on the boards of public companies, his investment experience and his scientific expertise and education qualify him to serve on our Board.
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INESE LOWENSTEIN | ​ | ​ | Age 49

Inese Lowenstein has served as a member of our Board since December 2021. Ms. Lowenstein has over 20 years of business and leadership experience in the life science, diagnostic and high-tech material industries. Ms. Lowenstein served in a part-time role as Senior Talent Advisor to Danaher Corporation from April 2021 to March 2022. Prior to her current role, Ms. Lowenstein was President of SCIEX, a Danaher company, from September 2017 to March 2021. Prior to her role as President, Ms. Lowenstein was the Senior Vice President of Global Sales & Service at SCIEX from August 2016 to September 2017. Prior to joining SCIEX, she held roles of increasing responsibility at Merck KGaA and EMD Millipore, most recently as an Executive Vice President, Head of Display Materials Business Unit. Ms. Lowenstein holds a Bachelor of Economics, Engineering Science from Riga Technical University, Latvia, and an M.B.A. from Walter A. Haas School of Business, University of California at Berkeley. We believe that Ms. Lowenstein’s extensive cross-industry and international business and leadership experience qualify her to serve on our Board.
VOTE REQUIRED
The proposal regarding the election of directors requires the approval of a plurality of the votes cast. This means that the two nominees receiving the highest number of affirmative “FOR” votes will be elected as Class I Directors. Votes withheld and broker non-votes will have no effect on the outcome of the vote on this proposal.
RECOMMENDATION OF THE BOARD OF DIRECTORS

| ​ | ​ | Our Board unanimously recommends a vote FOR the election of each of David Hirsch and Inese Lowenstein as Class I Directors to serve until the 2025 Annual Meeting of Stockholders and until their respective successors shall have been duly elected and qualified, or until their earlier death, resignation or removal.

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PROPOSAL 2: Ratification of Appointment of Independent Registered Public Accounting Firm
Our Audit Committee has appointed PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2022. Our Board has directed that this appointment be submitted to our stockholders for ratification. Although ratification of our appointment of PricewaterhouseCoopers LLP is not required by law or Nasdaq rules, we value the opinions of our stockholders and our Audit Committee believes that stockholder ratification of our appointment is a good corporate governance practice.
PricewaterhouseCoopers LLP has served as our independent registered public accounting firm since 2010. Neither PricewaterhouseCoopers LLP nor any of its members has any direct or indirect financial interest in or any connection with us in any capacity other than as our auditors, providing audit and non-audit related services.
A representative of PricewaterhouseCoopers LLP is expected to attend the Annual Meeting, have an opportunity to make a statement if he or she desires to do so, and be available to respond to appropriate questions from stockholders.
In the event that the appointment of PricewaterhouseCoopers LLP is not ratified by the stockholders, the Audit Committee will consider this fact when it appoints the independent registered public accounting firm for the fiscal year ending December 31, 2023. Even if the appointment of PricewaterhouseCoopers LLP is ratified, the Audit Committee retains the discretion to appoint a different independent registered public accounting firm at any time if it determines that such a change is in the interests of the Company.
VOTE REQUIRED
This proposal requires the approval of the affirmative vote of the holders of a majority in voting power of the votes cast affirmatively or negatively by the holders entitled to vote thereon. Abstentions will have no effect. Because brokers have discretionary authority to vote on the ratification of the appointment of PricewaterhouseCoopers LLP, we do not expect any broker non-votes in connection with this proposal.
RECOMMENDATION OF THE BOARD OF DIRECTORS

| ​ | ​ | The Board unanimously recommends a vote FOR the ratification of the appointment of PricewaterhouseCoopers LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2022.

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PART 2 - CORPORATE GOVERNANCE
GENERAL
Our Board has adopted Corporate Governance Guidelines, a Code of Business Conduct and Ethics and charters for our Nominating and Corporate Governance Committee, Audit Committee and Compensation Committee to assist the Board in the exercise of its responsibilities and to serve as a framework for the effective governance of Rapid Micro Biosystems. You can access our current committee charters, our Corporate Governance Guidelines and our Code of Business Conduct and Ethics in the “Corporate Governance” section of the “Investor Relations” page of our website located at investors.rapidmicrobio.com, or by writing to our Corporate Secretary at our offices at 1001 Pawtucket Boulevard West, Suite 280, Lowell, Massachusetts 01854. The inclusion of our website address in this proxy statement does not include or incorporate by reference the information on our website into this proxy statement, and you should not consider that information a part of this proxy statement.
BOARD COMPOSITION
Our Board currently consists of eight (8) members: David Hirsch, Richard Kollender, Melinda Litherland, Inese Lowenstein, Natale Ricciardi, Alexander Schmitz, Jeffrey Schwartz and Robert Spignesi. Our Board is currently divided into three classes with staggered, three-year terms. At each annual meeting of stockholders, the successor to each director whose term then expires will be elected to serve from the time of election and qualification until the third annual meeting following election or such director’s death, resignation or removal, whichever is earliest to occur. Any additional directorships resulting from an increase in the number of directors will be distributed among the three classes so that, as nearly as possible, each class will consist of one-third of the directors. The division of our Board into three classes with staggered three-year terms may delay or prevent a change of our management or a change in control of the Company. Our directors may be removed only for cause and only by the affirmative vote of the holders of at least two-thirds in voting power of the outstanding shares of capital stock of the Company entitled to vote at an election of directors.
DIRECTOR INDEPENDENCE
In March 2022, our Board undertook a review of the independence of each director and the composition of the Board and its committees. Based upon information requested from and provided by each director concerning his or her background, employment and affiliations, including family relationships, our Board has affirmatively determined that each of David Hirsch, Richard Kollender, Melinda Litherland, Inese Lowenstein, Natale Ricciardi, Alexander Schmitz and Jeffrey Schwartz is independent, as defined under the rules of the Nasdaq Stock Market LLC (“Nasdaq”). In making that determination, our Board considered the relationships that each director has with the Company and all other facts and circumstances the Board deemed relevant in determining independence, including the potential deemed beneficial ownership of our capital stock by each director and respective affiliations, including non-employee directors that are affiliated with certain of our major stockholders. We expect that the composition and functioning of our Board and each of the committees of the Board will continue to comply with all applicable requirements of Nasdaq and the rules and regulations of the SEC. There are no family relationships among any of our directors or executive officers. Under the applicable requirements of Nasdaq and the rules and regulations of the SEC, Richard Spignesi is not an independent director because he is currently employed as the president and chief executive officer of Rapid Micro Biosystems.
EXECUTIVE SESSIONS
The independent members of the Board meet in regularly scheduled executive sessions. Such meetings are presided over by the Chairperson of the Board, if the Chairperson of the Board qualifies as independent, or by the lead director, if the Chairperson of the Board does not qualify as independent.
DIRECTOR CANDIDATES
The Nominating and Corporate Governance Committee is responsible for identifying and reviewing the qualifications of potential director candidates and recommending to the Board those candidates to be nominated for election to the Board.
To facilitate the search process for director candidates, the Nominating and Corporate Governance Committee may solicit our current directors and executives for the names of potentially qualified candidates or may ask
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directors and executives to pursue their own business contacts for the names of potentially qualified candidates. The Nominating and Corporate Governance Committee may also consult with outside advisors or retain search firms to assist in the search for qualified candidates, or consider director candidates recommended by our stockholders. Once potential candidates are identified, the Nominating and Corporate Governance Committee reviews the backgrounds of those candidates, evaluates candidates’ independence from us and potential conflicts of interest, and determines if candidates meet the qualifications desired by the Nominating and Corporate Governance Committee of candidates for election as director.
In accordance with our Corporate Governance Guidelines, in evaluating the suitability of individual candidates, the Nominating and Corporate Governance Committee may take into account many factors, including: personal and professional integrity, ethics and values; experience in corporate management, such as serving as an officer or former officer of a publicly held company; strong finance experience; relevant social policy concerns; experience relevant to the Company’s industry; experience as a board member or executive officer of another publicly held company; relevant academic expertise or other proficiency in an area of the Company’s operations; diversity of expertise and experience in substantive matters pertaining to the Company’s business relative to other board members; diversity of background and perspective, including, but not limited to, with respect to gender, ethnicity, religion, nationality, disability, sexual orientation, place of residence, military service and specialized experience; practical and mature business judgment, including, but not limited to, the ability to make independent analytical inquiries; and any other relevant qualifications, attributes or skills. Our Corporate Governance Guidelines provide that the Board should evaluate each individual in the context of the Board as a whole, with the objective of assembling a group that can best perpetuate the success of the business and represent stockholder interests through the exercise of sound judgment using its diversity of experience in these various areas. The Nominating and Corporate Governance Committee assesses the effectiveness of its diversity policy in connection with its annual self-evaluation process.
Stockholders may recommend individuals to the Nominating and Corporate Governance Committee for consideration as potential director candidates by submitting the names of the recommended individuals, together with appropriate biographical information and background materials, to the Nominating and Corporate Governance Committee, c/o Secretary, Rapid Micro Biosystems, Inc., 1001 Pawtucket Boulevard West, Suite 280, Lowell, Massachusetts 01854. In the event there is a vacancy, and assuming that appropriate biographical and background material has been provided on a timely basis, the Nominating and Corporate Governance Committee will evaluate stockholder-recommended candidates by following substantially the same process, and applying substantially the same criteria, as it follows for candidates submitted by others.
COMMUNICATIONS WITH THE BOARD
Anyone who would like to communicate with, or otherwise make his or her concerns known directly to the Board, the chairperson of any of the Audit, Nominating and Corporate Governance, and Compensation Committees, or to the independent directors as a group, may do so by addressing such communications or concerns to the General Counsel of the Company, 1001 Pawtucket Boulevard West, Suite 280, Lowell, Massachusetts 01854, who will forward such communications to the appropriate party. In general, communications relating to corporate governance and long-term corporate strategy are more likely to be forwarded than communications relating to ordinary business affairs, personal grievances and matters as to which we tend to receive repetitive or duplicative communications. Such communications may be done confidentially or anonymously.
BOARD LEADERSHIP STRUCTURE AND ROLE IN RISK OVERSIGHT
Our Board exercises its discretion in combining or separating the roles of Chairperson of the Board and Chief Executive Officer as it deems appropriate in light of prevailing circumstances. We believe that we, like many U.S. companies, are well-served by a flexible leadership structure. Currently, Jeffrey Schwartz serves as Chairperson of the Board, and we have separated the position of the Chairperson of the Board and that of the Chief Executive Officer. While our Board believes the separation of these positions serves our Company well, the Board does not believe that it is appropriate to prohibit one person from serving as both Chairperson of the Board and Chief Executive Officer. Our Corporate Governance Guidelines provide the flexibility for our Board to modify our leadership structure in the future as it deems appropriate, and our Board will continue to consider whether the positions of Chairperson of the Board and Chief Executive Officer should be separated or combined at any given time as part of our succession planning process.
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Our Corporate Governance Guidelines provide that, if the Chairperson of the Board is a member of management or is a director that does not otherwise qualify as an independent director, the independent directors may elect a lead director whose responsibilities include presiding over all meetings of the Board at which the Chairperson is not present, including any executive sessions of the independent directors; approving meeting schedules and agendas; and acting as the liaison between the independent directors and the Chief Executive Officer and Chairperson of the Board, as appropriate. The full list of responsibilities of our lead director may be found in our Corporate Governance Guidelines. We currently do not have a lead director as the Chairperson of the Board is an independent director.
One of the key functions of our Board is informed oversight of our risk management process. Our Board does not have a standing risk management committee, but rather administers this oversight function directly through our Board as a whole, as well as through various standing committees of our Board that address risks inherent in their respective areas of oversight. In particular, our Board is responsible for monitoring and assessing strategic risk exposure and our Audit Committee has the responsibility to consider and discuss our major financial and cybersecurity risk exposures and the steps our management has taken to monitor and control these exposures, including guidelines and policies to govern the process by which risk assessment and management is undertaken. Our Audit Committee also monitors compliance with legal and regulatory requirements. Our Nominating and Corporate Governance Committee monitors the effectiveness of our corporate governance practices, including whether they are successful in preventing illegal or improper liability-creating conduct. Our Compensation Committee assesses and monitors whether any of our compensation policies and programs has the potential to encourage excessive risk-taking. While each committee is responsible for evaluating certain risks and overseeing the management of such risks, our entire Board is regularly informed through committee reports about such risks.
ANTI-HEDGING POLICY
Our Board has adopted an Insider Trading Compliance Policy, which applies to all of our directors, officers and employees. The policy prohibits our directors, officers and employees and any entities they control from engaging in transactions in publicly traded options related to the Company’s equity securities, such as puts or calls, or engaging in transactions involving any other financial instruments, such as prepaid variable forward contracts, equity swaps, collars or exchange funds, that hedge or offset, or are designed to hedge or offset, any decrease in the market value of the Company’s equity securities.
CODE OF ETHICS
We have adopted a written Code of Business Conduct and Ethics that applies to our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. Our Code of Business Conduct and Ethics is available under the Corporate Governance section of the “Investor Relations” page of our website at investors.rapidmicrobio.com. In addition, we intend to post on our website all disclosures that are required by law or the Nasdaq rules concerning any amendments to, or waivers from, any provision of the code.
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PART 3 – BOARD OF DIRECTORS
BOARD OF DIRECTORS
The following table sets forth our current directors, as of the date of this proxy statement, including two of our current directors who are nominated for re-election at the 2022 Annual Meeting.

Name | ​ | ​ | Age | ​ | ​ | Positions with Rapid Micro Biosystems | ​ | ​ | Class
David Hirsch, M.D., Ph.D. | ​ | ​ | 51 | ​ | ​ | Director | ​ | ​ | I
Richard Kollender | ​ | ​ | 52 | ​ | ​ | Director | ​ | ​ | II
Melinda Litherland | ​ | ​ | 64 | ​ | ​ | Director | ​ | ​ | III
Inese Lowenstein | ​ | ​ | 49 | ​ | ​ | Director | ​ | ​ | I
Natale Ricciardi | ​ | ​ | 73 | ​ | ​ | Director | ​ | ​ | II
Alexander Schmitz | ​ | ​ | 47 | ​ | ​ | Director | ​ | ​ | I
Jeffrey Schwartz | ​ | ​ | 43 | ​ | ​ | Director, Chairperson | ​ | ​ | II
Robert Spignesi | ​ | ​ | 53 | ​ | ​ | Director, President and Chief Executive Officer | ​ | ​ | III

In March 2022, we announced that Alexander Schmitz would not stand for re-election at the 2022 Annual Meeting, and therefore, our Board has nominated all other Class I directors other than Alexander Schmitz for re-election to three-year terms at the 2022 Annual Meeting.
Further the biographical description below for each director nominee includes the specific experience, qualifications, skills, attributes and characteristics that led to the decision of our Board that such person should serve as a director of Rapid Micro Biosystems.
CURRENT CLASS I DIRECTORS:
(CURRENT TERMS TO EXPIRE AT THE 2022 ANNUAL MEETING)
The current members of the Board who are Class I Directors are as follows:

Name | ​ | ​ | Served as a Director Since | ​ | ​ | Positions with Rapid Micro Biosystems
David Hirsch, M.D., Ph.D. | ​ | ​ | 2013 | ​ | ​ | Director
Alexander Schmitz | ​ | ​ | 2020 | ​ | ​ | Director
Inese Lowenstein | ​ | ​ | 2021 | ​ | ​ | Director

The principal occupations and business experience, for at least the past five years, of each Class I Director, as of April 8, 2022, are as follows:

DAVID HIRSCH, M.D., Ph.D. | ​ | ​ | Age 51

See biography, which is set forth above under “Nominees for Class I Directors” on page 10 of this proxy statement.

INESE LOWENSTEIN | ​ | ​ | Age 49

See biography, which is set forth above under “Nominees for Class I Directors” on page 10 of this proxy statement.

ALEXANDER SCHMITZ | ​ | ​ | Age 47

Alexander Schmitz has served as a member of our Board since May 2020. Mr. Schmitz currently serves as a Partner at Endeavour Vision Ltd., a private equity firm, where he has worked since 2015, investing in growth-stage medical device and digital health companies. Mr. Schmitz holds an M.B.A. from INSEAD and a B.S.F.S. in International Economics from Georgetown University. We believe that Mr. Schmitz’s industry knowledge and investment experience qualify him to serve on our Board. Mr. Schmitz’s term as a director expires at the Annual Meeting and he has informed the Company that he has decided not to stand for re-election.
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Mr. Schmitz plans to serve out his current term as a member of the Board, Audit Committee and Compensation Committee until the Annual Meeting. His decision not to stand for re-election was not the result of any disagreement with the Company, including with respect to any matter relating to the company’s operations, policies or practices.
CONTINUING MEMBERS OF THE BOARD OF DIRECTORS:
CLASS II DIRECTORS (TERMS TO EXPIRE AT THE 2023 ANNUAL MEETING)
The current members of the Board who are Class II Directors are as follows:

Name | ​ | ​ | Served as a Director Since | ​ | ​ | Positions with Rapid Micro Biosystems
Jeffrey Schwartz | ​ | ​ | 2018 | ​ | ​ | Director, Chairperson
Richard Kollender | ​ | ​ | 2009(1) | ​ | ​ | Director
Natale Ricciardi | ​ | ​ | 2016 | ​ | ​ | Director

(1) | Mr. Kollender has served as a director since 2009, except for the period from February 2017 to October 2018.

The principal occupations and business experience, for at least the past five years, of each Class II Director, as of April 8, 2022, are as follows:

JEFFREY SCHWARTZ | ​ | ​ | Age 43

Jeffrey Schwartz has served as a member of our Board and Chairperson since April 2018. Mr. Schwartz currently serves as a managing director of Bain Capital Life Sciences, LP, where he is a founding member, and since August 2020 has served as Chief Executive Officer of BCLS Acquisition Corp., a special purpose acquisition company sponsored by an affiliate of Bain Capital Life Sciences, LP. Prior to founding Bain Capital Life Sciences in 2016, he was a leader within the healthcare vertical of Bain Capital Private Equity, LP. Mr. Schwartz has also served on the boards of directors of SpringWorks Therapeutics, Inc. since August 2017 and BCLS Acquisition Corp since August 2020. Mr. Schwartz holds an M.B.A. from the Wharton School at the University of Pennsylvania, where he was a Palmer Scholar, and holds a B.A. in economics from Yale University. We believe that Mr. Schwartz’s extensive industry and transactional experience qualify him to serve on our Board.

RICHARD KOLLENDER | ​ | ​ | Age 52

Richard Kollender has served as a member of our Board since July 2009, except for the period from February 2017 to October 2018. From August 2016 to September 2018, Mr. Kollender served as our Chief Business Officer and Chief Financial Officer. Since April 2022, Mr. Kollender has served as the Chief Financial Officer and Chief Business Officer of Reaction Biology Corporation. Mr. Kollender served on the board of directors of Strongbridge Biopharma plc, a biopharmaceutical company, from March 2015 to September 2019, where he also served as Chief Operating Officer from September 2019 to March 2021, and as President and Chief Financial Officer from March 2021 to March 2022. Strongbridge Biopharma plc was acquired by Xeris Pharmaceuticals Inc. in October of 2021 and Mr. Kollender agreed to remain with the company through March 2022. Since January 2011, he has served as a Partner and Executive Manager of Quaker Partners Management, LP, a healthcare investment firm, which he initially joined in 2003. Mr. Kollender previously served as a director of Celator Pharmaceuticals, Inc., currently a subsidiary of Jazz Pharmaceuticals plc, Nupathe, Inc., and Insmed, Inc. Mr. Kollender holds a B.A. in accounting from Franklin and Marshall College and an M.B.A. and a certificate degree in the graduate program in health administration and policy from the University of Chicago. We believe that Mr. Kollender’s knowledge of our company and experience in the industry qualify him to serve on our Board.

NATALE RICCIARDI | ​ | ​ | Age 73

Natale Ricciardi has served as a member of our Board since March 2016. Mr. Ricciardi spent his entire 39-year career at Pfizer Inc., a biopharmaceutical company, retiring in 2011 as a member of the Pfizer Executive Leadership Team. While holding the positions of President, Pfizer Global Manufacturing, and Senior Vice President of Pfizer Inc. from 2004 until 2011, Mr. Ricciardi was directly responsible for all of Pfizer’s internal and external supply organization. Mr. Ricciardi maintained responsibility for global manufacturing activities from
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2004 through 2011. Previously, from 1999 to 2004, he had oversight for Pfizer’s U.S. manufacturing operations and from 1995 to 1999 was Vice President of Manufacturing for Pfizer’s Animal Health Group. Mr. Ricciardi has served on the board of directors of Dynavax Technologies Corporation since July 2013 and Prestige Consumer Healthcare, Inc. since May 2016. Mr. Ricciardi holds an M.B.A. in Finance and International Business from Fordham University and a Bachelor of Engineering in Chemical Engineering from The City College of New York. We believe that Mr. Ricciardi’s extensive experience at Pfizer and his experience serving on boards of various life sciences companies qualify him to serve on our Board.
CONTINUING MEMBERS OF THE BOARD OF DIRECTORS:
CLASS III DIRECTORS (TERMS TO EXPIRE AT THE 2024 ANNUAL MEETING)
The current members of the Board who are Class III Directors are as follows:

Name | ​ | ​ | Served as a Director Since | ​ | ​ | Positions with Rapid Micro Biosystems
Melinda Litherland | ​ | ​ | 2021 | ​ | ​ | Director
Robert Spignesi | ​ | ​ | 2014 | ​ | ​ | President and Chief Executive Officer and Director

The principal occupations and business experience, for at least the past five years, of each Class III Director, as of April 8, 2022, are as follows:

MELINDA LITHERLAND | ​ | ​ | Age 64

Melinda Litherland has served as a member of our Board since June 2021. Ms. Litherland currently serves on the board of directors of Bio-Rad Laboratories, Inc., where she has served since April 2017. Ms. Litherland retired in 2015 as a Partner at Deloitte & Touche LLP. During her 34 years at Deloitte & Touche LLP, she worked primarily with technology and life science companies in both audit and consulting capacities. Ms. Litherland holds a B.A. in Economics from Rice University and a Master of Accounting from the Rice University Jones Graduate School of Business. Ms. Litherland is a certified public accountant and a member of the American Institute of CPAs (AICPA). We believe that Ms. Litherland’s extensive financial and life sciences background qualifies her to serve on our Board.

ROBERT SPIGNESI | ​ | ​ | Age 53

Robert Spignesi has served as our President and Chief Executive Officer since October 2014 and as a member of our Board since October 2014. Previously, Mr. Spignesi served as the Vice President & General Manager, Americas of the Microbiology Division at Thermo Fisher Scientific and the Vice President of Global Strategy, Business Development and Marketing at Fisher Scientific. Earlier in his career, he served as an Aviation Officer with the U.S. Army. Mr. Spignesi holds an M.B.A. from Columbia University and a B.S. in Economics from the United States Military Academy at West Point. We believe that Mr. Spignesi’s role as Chief Executive Officer of our company and broad industry experience qualify him to serve on our Board.
We believe that all of our current Board members and nominees for Class I directors possess the professional and personal qualifications necessary for Board service, and have highlighted particularly noteworthy attributes for each Board member and nominee in the individual biographies above.
There are no family relationships between or among any of our directors. The principal occupation and employment during the past five years of each of our directors was carried on, in each case except as specifically identified above, with a corporation or organization that is not a parent, subsidiary or other affiliate of us. There is no arrangement or understanding between any of our directors and any other person or persons pursuant to which he or she is to be selected as a director.
There are no material legal proceedings to which any of our directors is a party adverse to us or any of our subsidiaries or in which any such director has a material interest adverse to us
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BOARD DIVERSITY MATRIX
The composition of our Board currently includes two individuals who are diverse under the Nasdaq Listing Rule 5605(f) regarding board diversity, representing gender diversity of 25%, as presented in the below Board Diversity Matrix. Under Nasdaq Listing Rule 5605(f), directors who self-identify as (i) female, (ii) an underrepresented minority or (iii) LGBTQ+ are defined as being diverse. The following chart summarizes certain self-identified personal characteristics of our directors, in accordance with Nasdaq Listing Rule 5605(f). Each term used in the table has the meaning given to it in the rule and related instructions.

Board Diversity Matrix (As of April 8, 2022)
Total Number of Directors | ​ | ​ | 8
| ​ | ​ | Female | ​ | ​ | Male | ​ | ​ | Non-Binary | ​ | ​ | Did Not Disclose Gender
Part I: Gender Identity | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |
Directors | ​ | ​ | 2 | ​ | ​ | 6 | ​ | ​ | — | ​ | ​ | —
Part II: Demographic Background | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |
African American or Black | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Alaskan Native or Native American | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Asian | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Hispanic or Latinx | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Native Hawaiian or Pacific Islander | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
White | ​ | ​ | 2 | ​ | ​ | 6 | ​ | ​ | — | ​ | ​ | —
Two or More Races or Ethnicities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
LGBTQ+ | ​ | ​ | —
Did Not Disclose Demographic Background | ​ | ​ | —
Directors who are Military Veterans | ​ | ​ | 1

ATTENDANCE BY MEMBERS OF THE BOARD OF DIRECTORS AT MEETINGS
There were six (6) meetings of the Board during the fiscal year ended December 31, 2021. During the fiscal year ended December 31, 2021, each director attended at least 75% of the aggregate of (i) all meetings of the Board and (ii) all meetings of the committees on which the director served during the period in which he or she served as a director.
Under our Corporate Governance Guidelines, which is available on our website at investors.rapidmicrobio.com, a director is expected to spend the time and effort necessary to properly discharge his or her responsibilities. Accordingly, a director is expected to regularly prepare for and attend meetings of the Board and all committees on which the director sits (including separate meetings of the independent directors), with the understanding that, on occasion, a director may be unable to attend a meeting. A director who is unable to attend a meeting of the Board or a committee of the Board is expected to notify the Chairperson of the Board or the Chairperson of the appropriate committee in advance of such meeting, and, whenever possible, participate in such meeting via teleconference in the case of an in-person meeting. We do not maintain a formal policy regarding director attendance at the Annual Meeting; however, it is expected that, absent compelling circumstances, directors will attend. We did not hold an annual meeting of stockholders in 2021. This annual meeting will be our first annual meeting of our stockholders as a public company.
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Committees of the Board
Our Board has established three standing committees—Audit, Compensation and Nominating and Corporate Governance—each of which operates under a written charter that has been approved by our Board.
The members of each of the Board committees are set forth in the following chart.

Name | ​ | ​ | Audit | ​ | ​ | Compensation | ​ | ​ | Nominating and Corporate Governance
David Hirsch, M.D., Ph.D. | ​ | ​ |  | ​ | ​ | Chair | ​ | ​ |
Richard Kollender | ​ | ​ | X | ​ | ​ |  | ​ | ​ | X
Melinda Litherland | ​ | ​ | Chair | ​ | ​ |  | ​ | ​ |
Inese Lowenstein | ​ | ​ | X | ​ | ​ | X | ​ | ​ |
Natale Ricciardi | ​ | ​ |  | ​ | ​ | X | ​ | ​ | X
Alexander Schmitz | ​ | ​ | X | ​ | ​ | X | ​ | ​ |
Jeffrey Schwartz | ​ | ​ |  | ​ | ​ |  | ​ | ​ | Chair
Robert Spignesi | ​ | ​ |  | ​ | ​ |  | ​ | ​ |

AUDIT COMMITTEE
The Audit Committee’s responsibilities include, among other things:

• | appointing, approving the compensation of, and assessing the independence of our registered public accounting firm;

• | overseeing the work of our independent registered public accounting firm, including through the receipt and consideration of reports from such firm;

• | reviewing and discussing with management and the independent registered public accounting firm our annual and quarterly financial statements and related disclosures as well as critical accounting policies and practices used by us;

• | coordinating our Board’s oversight of our internal control over financial reporting, disclosure controls and procedures and code of business conduct and ethics;

• | discussing our risk management policies, including cyber risk;

• | meeting independently with our internal auditing staff, if any, independent registered public accounting firm and management;

• | reviewing and approving or ratifying any related person transactions; and

• | preparing the audit committee report required by SEC rules.

The Audit Committee charter is available on our website at investors.rapidmicrobio.com. The members of our Audit Committee are Melinda Litherland, Richard Kollender, Inese Lowenstein and Alexander Schmitz. Melinda Litherland serves as the Chairperson of the committee. All members of our Audit Committee meet the requirements for financial literacy under the applicable listing rules of Nasdaq, or the Nasdaq rules. Our Board has determined that Melinda Litherland, Richard Kollender, Inese Lowenstein and Alexander Schmitz meet the independence requirements of Rule 10A-3 under the Exchange Act. We previously relied on the phase-in schedules set forth in Nasdaq listing rule 5615(b)(1) with respect to Mr. Kollender’s service on our Audit Committee due to his prior employment with the Company. Upon review in March 2022, our Board determined that Melinda Litherland, Inese Lowenstein, Richard Kollender and Alexander Schmitz meet the independence requirements of the Nasdaq rules for audit committee purposes. As our Audit Committee is composed entirely of members of our Board who satisfy the standards of independence established under the Nasdaq rules, we no longer rely on the phase-in schedules of the Nasdaq rules. Our Board has determined that Melinda Litherland is an “audit committee financial expert” as defined by applicable SEC rules and has the requisite financial sophistication as defined under the applicable Nasdaq rules.
The Audit Committee met five (5) times during the fiscal year ended December 31, 2021.
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COMPENSATION COMMITTEE
The Compensation Committee’s responsibilities include, among other things:

• | reviewing and making recommendations to our Board with respect to the compensation of our Chief Executive Officer;

• | reviewing and approving, the compensation of our other executive officers;

• | overseeing and administering our cash and equity incentive plans;

• | reviewing and making recommendations to our Board with respect to director compensation;

• | approving the retention of any consulting firm or outside advisor to assist in the evaluation of compensation matters;

• | reviewing and discussing annually with management our “Compensation Discussion and Analysis,” to the extent required; and

• | preparing the annual compensation committee report required by SEC rules, to the extent required.

The Compensation Committee charter is available on our website at investors.rapidmicrobio.com. The members of our Compensation Committee are David Hirsch, Inese Lowenstein, Natale Ricciardi and Alexander Schmitz. David Hirsch serves as the Chairperson of the Compensation Committee. Our Board has determined that each of David Hirsch, Inese Lowenstein, Natale Ricciardi and Alexander Schmitz is independent under the applicable Nasdaq rules, including the Nasdaq rules specific to membership on the compensation committee, and is a “non-employee director” as defined in Rule 16b-3 promulgated under the Exchange Act. The Compensation Committee may delegate its authority under its charter to a subcommittee as it deems appropriate from time to time.
The Compensation Committee met three (3) times during the fiscal year ended December 31, 2021.
Compensation Consultants
In fiscal year 2021, prior to our initial public offering and the formation of our Compensation Committee, our management engaged Radford, an Aon company (“Radford”), to provide compensation consulting services. Since our initial public offering and the establishment of our Compensation Committee, Radford has continued to serve as compensation consultant to management and the Compensation Committee. During fiscal year 2021, Radford’s services included advising on equity compensation programs and the development of the Company’s peer group and providing support and analysis regarding executive and director compensation. Radford also performed sales compensation and general employee salary and benefit consulting services for the Company in 2021, and the Company paid Radford approximately $139,321 in 2021 for these services. Our Compensation Committee has assessed the independence of Radford consistent with SEC rules and Nasdaq listing standards and has concluded that the engagement of Radford does not raise any conflict of interest.
NOMINATING AND CORPORATE GOVERNANCE COMMITTEE
The Nominating and Corporate Governance Committee’s responsibilities include, among other things:

• | identifying individuals qualified to become board members;

• | recommending to our Board the persons to be nominated for election as directors and to each Board committee;

• | developing and recommending to our Board corporate governance guidelines, and reviewing and recommending to our Board proposed changes to our corporate governance guidelines from time to time, including in connection with environmental, social and governance (ESG) considerations and corporate social responsibility (CSR) initiatives; and

• | overseeing a periodic evaluation of our Board.

The Nominating and Corporate Governance Committee charter is available on our website at investors.rapidmicrobio.com. The members of our Nominating and Corporate Governance Committee are Jeffrey Schwartz, Richard Kollender and Natale Ricciardi. Jeffrey Schwartz serves as the Chairperson of the Nominating
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and Corporate Governance Committee. We previously relied on the phase-in schedules of Nasdaq listing rule 5615(b)(1) with respect to Mr. Kollender’s service on our Nominating and Corporate Governance Committee due to his prior employment with the Company. Upon review in March 2022, our Board determined that Jeffrey Schwartz, Richard Kollender and Natale Ricciardi meet the independence requirements of the Nasdaq rules for nominations committee purposes. As our Nominating and Corporate Governance Committee is composed entirely of members of our Board who satisfy the standards of independence established under the Nasdaq rules, we no longer rely on the phase-in schedules of the Nasdaq rules.
The Nominating and Corporate Governance Committee did not meet during the fiscal year ended December 31, 2021.
DIRECTOR COMPENSATION
The following table sets forth a summary of the compensation earned by our directors for the year ended December 31, 2021, with the exception of Mr. Spignesi, who does not receive compensation for service on our Board and whose compensation is included in the “Summary Compensation Table” above under “Executive Compensation.” Other than as set forth in the table below, we did not pay any compensation or make any equity awards to our non-employee directors during the fiscal year ended December 31, 2021.
2021 DIRECTOR COMPENSATION TABLE

Name | ​ | ​ | Fees Earned or Paid in Cash ($)(1) | ​ | ​ | Option Awards ($)(2) | ​ | ​ | Total ($)
Bruce Cohen(3) | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
David Hirsch, M.D., Ph.D. | ​ | ​ | 27,000 | ​ | ​ | 208,260 | ​ | ​ | 235,260
Richard Kollender | ​ | ​ | 27,500 | ​ | ​ | 208,260 | ​ | ​ | 235,760
Melinda Litherland(4) | ​ | ​ | 30,000 | ​ | ​ | 208,260 | ​ | ​ | 238,260
Inese Lowenstein(5) | ​ | ​ | 3,333 | ​ | ​ | 117,268 | ​ | ​ | 120,601
Natale Ricciardi | ​ | ​ | 41,000(6) | ​ | ​ | 208,260 | ​ | ​ | 249,260
Alexander Schmitz | ​ | ​ | 28,500 | ​ | ​ | 208,260 | ​ | ​ | 236,760
Jeffrey Schwartz | ​ | ​ | 45,000 | ​ | ​ | 208,260 | ​ | ​ | 253,260

(1) | Includes prorated fees for service on our public company Board from the quarter beginning July 1, 2021, the period during which the effectiveness of our registration statement filed in connection with our initial public offering, through December 31, 2021.

(2) | The amounts reported in the “Option Awards” Column reflect the aggregate fair value of stock-based compensation awarded during the year computed in accordance with the provisions of FASB Accounting Standard Codification Topic 718. See Note 13 to our audited financial statements appearing in our 2021 Annual Report on Form 10-K, which was filed with the SEC on March 24, 2022, regarding assumptions underlying the valuation of equity awards.

(3) | Mr. Cohen resigned from our Board effective July 14, 2021.

(4) | Ms. Litherland was appointed to our Board effective June 24, 2021.

(5) | Ms. Lowenstein was appointed to our Board effective December 17, 2021 and had prorated fees for service based on her start date.

(6) | Includes prorated fees for service as a non-employee director who was not affiliated with one of our investors on our private company board of directors from the period beginning January 1, 2021 until the effective date of our registration statement filed in connection with our initial public offering.

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The table below shows the aggregate numbers of option awards (exercisable and unexercisable) held as of December 31, 2021 by each non-employee director. None of our non-employee directors held any stock awards as of December 31, 2021.

Name | ​ | ​ | Option Awards Outstanding at 2021 Fiscal Year-End
Bruce Cohen | ​ | ​ | 0(1)
David Hirsch, M.D., Ph.D. | ​ | ​ | 25,000(2)
Richard Kollender | ​ | ​ | 187,085(3)
Melinda Litherland | ​ | ​ | 25,000(2)
Inese Lowenstein | ​ | ​ | 25,000(4)
Natale Ricciardi | ​ | ​ | 85,042(5)
Alexander Schmitz | ​ | ​ | 25,000(2)
Jeffrey Schwartz | ​ | ​ | 25,000(2)

(1) | As of December 31, 2021, Mr. Cohen did not hold any exercisable or unexercisable equity grants.

(2) | As of December 31, 2021, Ms. Litherland, Dr. Hirsch and Messrs. Schmitz and Schwartz held stock options to purchase an aggregate of 25,000 shares of Class A common stock, of which 3,472 were vested. Unvested shares underlying options held by Ms. Litherland, Dr. Hirsch and Messrs. Schmitz and Schwartz are scheduled to vest in equal monthly installments ending July 14, 2024 subject to continued service as a non-employee director as of the applicable vesting date, provided that each option will vest in full upon a change in control to the extent then-outstanding.

(3) | As of December 31, 2021, Mr. Kollender held stock options to purchase an aggregate of 187,085 shares of Class A common stock, of which 165,557 were vested. Unvested shares underlying Mr. Kollender’s options are scheduled to vest in equal monthly installments ending July 14, 2024 subject to continued service as a non-employee director as of the applicable vesting date, provided that each option will vest in full upon a change in control to the extent then-outstanding.

(4) | As of December 31, 2021, Ms. Lowenstein held stock options to purchase an aggregate of 25,000 shares of Class A common stock, of which no shares were vested. Unvested shares underlying Ms. Lowenstein’s options are scheduled to vest in equal monthly installments ending December 17, 2024 subject to continued service as a non-employee director as of the applicable vesting date, provided that each option will vest in full upon a change in control to the extent then-outstanding.

(5) | As of December 31, 2021, Mr. Ricciardi held stock options to purchase an aggregate of 85,042 shares of Class A common stock, of which 59,944 were vested. Unvested shares underlying Mr. Ricciardi’s options consist of (i) 3,570 shares which are scheduled to vest in equal monthly installments ending April 12, 2022, and (ii) 21,528 shares that are scheduled to vest in equal monthly installments ending July 14, 2024, subject to continued service as a non-employee director as of the applicable vesting date, provided that each option will vest in full upon a change in control to the extent then-outstanding.

Our Board approved the grant of options to purchase 25,000 shares of our Class A common stock pursuant to the Rapid Micro Biosystems, Inc. 2021 Incentive Award Plan (the “2021 Plan”) to each of Jeffrey Schwartz, David Hirsch, Melinda Litherland, Richard Kollender, Natale Ricciardi and Alexander Schmitz. These option grants became effective upon the effectiveness of the registration statement filed in connection with our initial public offering and have an exercise price equal to the initial price to the public our Class A common stock in our initial public offering. Each option will vest in 36 equal monthly installments following the grant date, subject to continued service as a non-employee director as of the applicable vesting date, provided that each option will vest in full upon a change in control to the extent then-outstanding. In addition, on December 17, 2021, in connection with her appointment as a Director, our Board approved the grant of options to purchase 25,000 shares of our Class A common stock pursuant to the 2021 Plan to Inese Lowenstein, which is subject to the foregoing vesting terms.
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NON-EMPLOYEE DIRECTOR COMPENSATION PROGRAM
Our Board adopted, and our stockholders approved, a non-employee director compensation program pursuant to which our non-employee directors will be entitled to the cash and equity compensation described below. The compensation payable under the program is intended to be competitive in relation to both the market in which the company operates and the nature, complexity and size of the company’s business.
Our non-employee directors received the following amounts for their services on our board under the non-employee director compensation program:
Cash Compensation

• | An annual director fee of $40,000;

• | If the director serves as lead independent director or chair or on a committee of our board, an additional annual fee as follows:

○ | Chair of the board or lead independent director, $40,000;

○ | Chair of the audit committee, $20,000;

○ | Audit committee member other than the chair, $10,000;

○ | Chair of the compensation committee, $14,000;

○ | Compensation committee member other than the chair, $7,000;

○ | Chair of the nominating and corporate governance committee, $10,000;

○ | Nominating and corporate governance committee member other than the chair, $5,000.

Director fees are payable quarterly in arrears, provided that the amount of each payment will be prorated for any portion of a quarter that a director is not serving on our board.
Equity Compensation

• | Initial Awards: Each non-employee director who is initially elected or appointed to serve on our Board after the effective date of the non-employee director compensation program automatically will be granted, on the date on which such non-employee director is appointed or elected to serve on the board, an option to purchase 25,000 shares of our Class A common stock with an exercise price per share of Class A common stock equal to the fair market value of a share of our Class A common stock on the date of grant. These initial options will vest in 36 equal monthly installments following the date of grant, such that the initial options will be fully vested and exercisable on the third anniversary of the date of grant, subject to the non-employee director’s continued service as a non-employee director through the applicable vesting date.

• | Subsequent Awards: Each non-employee director who (i) has been serving on our Board for at least six months as of the date of any annual meeting of our stockholders after the initial public offering and (ii) will continue to serve as a director immediately following such meeting automatically will be granted, on such annual meeting date, an option to purchase 12,500 shares of our Class A common stock with an exercise price per share of Class A common stock equal to the fair market value of a share of our Class A common stock on the date of grant. Each such annual option will vest in full on the earlier to occur of (i) the first anniversary of the applicable grant date and (ii) the date of the next annual meeting following the grant date, subject to such non-employee director’s continued service as a non-employee director through the applicable vesting date.

In addition, each initial option and annual option will vest in full upon a change in control of the company (as defined in the 2021 Plan). If a non-employee director’s service as a non-employee director on our board terminates for any reason, unless the board determines otherwise, such director’s awards that are outstanding and unexercisable at the time of such termination will be forfeited and will not become thereafter vested or thereafter exercisable.
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PART 4 - EXECUTIVE OFFICERS
Our Leadership Team
The following table sets forth our executive officers and the positions currently held by each such person within Rapid Micro Biosystems and the biographical descriptions below outline the relevant experience, qualifications, attributes and skills of each executive officer, as of April 8, 2022.

Name | ​ | ​ | Age | ​ | ​ | Position
Robert Spignesi(1) | ​ | ​ | 53 | ​ | ​ | President and Chief Executive Officer and Director
Sean Wirtjes(2) | ​ | ​ | 52 | ​ | ​ | Chief Financial Officer
Richard Keys(3) | ​ | ​ | 51 | ​ | ​ | Chief Commercial Officer
Jonathan Paris(4) | ​ | ​ | 47 | ​ | ​ | Senior Vice President, Secretary and General Counsel
Victoria Vezina(5) | ​ | ​ | 54 | ​ | ​ | Chief Human Resources Officer
John Wilson(6) | ​ | ​ | 54 | ​ | ​ | Chief Operating Officer

(1) | See biography, which is set forth above under “Board of Directors” on page 18 of this proxy statement.

(2) | Sean Wirtjes has served as our Chief Financial Officer since September 2018. From August 2012 to July 2016, Mr. Wirtjes served as the Vice President, Finance and Controller of the Asia Pacific, Middle East and Africa region for Boston Scientific Corporation, a manufacturer of medical devices, where he led all aspects of financial management for the region. Mr. Wirtjes holds a B.S. in Accounting from the Carroll School of Management at Boston College.

(3) | Richard Keys has served as our Chief Commercial Officer since October 2021. Prior to joining the company, Mr. Keys was Senior Vice President, Global Commercial Operations at Quanterix Corporation from April 2019 to September 2021. From August 2013 to April 2019, Mr. Keys was the director of North American Sales at SomaLogic Inc. and from October 2007 to July 2013, he worked as a sales professional at Molecular Devises, LLC. Mr. Keys served his country with the U.S. Navy. He also holds a Master’s degree in Biomedical Science from University of Massachusetts Medical School and a B.A. in Chemistry from Southern Illinois University.

(4) | Jonathan Paris has served as our Senior Vice President, Secretary and General Counsel since May 2021. From September 2015 to May 2021, Mr. Paris served as the Deputy General Counsel at Insulet Corporation, a medical device company. Prior to that, Mr. Paris also served as an Associate General Counsel at Covidien plc from July 2009 to February 2015 and at Medtronic plc from February 2015 to September 2015. Mr. Paris holds a J.D. from Suffolk University Law School, an M.S.F. from Suffolk University Sawyer Business School and a B.A. in Economics and Government from Colby College.

(5) | Victoria Vezina has served as our Chief Human Resources Officer since September 2020. From May 2019 to June 2020, Ms. Vezina served as the Chief People Officer at SimpliSafe, Inc., a home security company. Ms. Vezina also served as Head of Global Services HR at The Boston Consulting Group, a management consulting firm, from May 2016 to March 2019. From December 2013 to July 2015, Mr. Vezina served as Chief Human Resources Officer for Skyworks, Inc. Ms. Vezina holds an M.A. in Organizational Psychology from William James College and a B.A. in Government from Clark University.

(6) | John Wilson has served as our Chief Operating Officer since January 2021. From November 2010 to January 2021, Mr. Wilson served in various roles at Becton Dickinson and Company, a medical technology company, including Vice President of Global Operations, Director of Operational Excellence, Vice President of Manufacturing and Plant Manager, where he led manufacturing activities worldwide to ensure the quality, supply, and delivery of product for Becton Dickinson. Mr. Wilson holds an M.B.A. from the University of San Francisco and a B.S. in Business Management from the University of Phoenix.

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Executive Compensation
The following section discusses the material components of the executive compensation program for our executive officers who are named in the “2021 Summary Compensation Table” below. In 2021, our “named executive officers” were as follows:

• | Robert Spignesi, Chief Executive Officer;

• | Sean Wirtjes, Chief Financial Officer; and

• | Richard Keys, Chief Commercial Officer.

2021 Summary Compensation Table
The following table sets forth summary information concerning the compensation of our named executive officers for the years ended December 31, 2020 and 2021:

Name and Principal Position | ​ | ​ | Year | ​ | ​ | Salary ($) | ​ | ​ | Bonus ($) | ​ | ​ | Option Awards ($)(1)(2) | ​ | ​ | Non-Equity Incentive Plan Compensation ($)(3) | ​ | ​ | All Other Compensation ($) | ​ | ​ | Total ($)
Robert Spignesi Chief Executive Officer | ​ | ​ | 2021 | ​ | ​ | 507,317 | ​ | ​ | — | ​ | ​ | 575,871 | ​ | ​ | 342,000 | ​ | ​ | 34,350(4) | ​ | ​ | 1,459,538
​ | 2020 | ​ | ​ | 445,228 | ​ | ​ | — | ​ | ​ | 301,770 | ​ | ​ | 311,644 | ​ | ​ | 32,190 | ​ | ​ | 1,090,832
Sean Wirtjes Chief Financial Officer | ​ | ​ | 2021 | ​ | ​ | 372,518 | ​ | ​ | — | ​ | ​ | 115,384 | ​ | ​ | 150,000 | ​ | ​ | 32,191(5) | ​ | ​ | 670,093
​ | 2020 | ​ | ​ | 342,531 | ​ | ​ | — | ​ | ​ | 59,485 | ​ | ​ | 180,261 | ​ | ​ | 31,551 | ​ | ​ | 613,828
Richard Keys(6) Chief Commercial Officer | ​ | ​ | 2021 | ​ | ​ | 102,058 | ​ | ​ | 75,000(7) | ​ | ​ | 1,409,850 | ​ | ​ | 40,670 | ​ | ​ | 10,100(8) | ​ | ​ | 1,637,678

(1) | The amounts represent the full grant-date fair value of the option awards to named executive officers, calculated in accordance with FASB ASC Topic 718. Such grant date fair value does not take into account any estimated forfeitures related to service-based vesting conditions. The assumptions used to calculate the grant-date fair value of option awards made to executive officers are set forth in Note 13 to our consolidated financial statements included in our Annual Report on Form 10-K. for the fiscal year ended December 31, 2021, as filed with the SEC on March 24, 2022. The amounts reported in this column reflect the accounting cost for these options and do not correspond to the actual economic value that may be received by the named executive officers upon exercise of the options.

(2) | The vesting schedule can be found in the “Outstanding Equity Awards at 2021 Fiscal Year-End” table.

(3) | For 2021, the amounts represent performance-based annual cash bonuses earned based on corporate and individual performance during 2021 in the amount of $342,000 for Mr. Spignesi, $150,000 for Mr. Wirtjes and $40,670 for Mr. Keys.

(4) | Such amount includes $5,191 in the Company’s matching contributions under our 401(k) Savings and Investment Plan, and $29,159 in insurance premiums that we paid in respect of Mr. Spignesi.

(5) | Such amount includes $3,032 in the Company’s matching contributions under our 401(k) Savings and Investment Plan, and $29,159 in insurance premiums that we paid in respect of Mr. Wirtjes.

(6) | Mr. Keys joined us on October 1, 2021. The amount reported represents Mr. Keys’ pro-rated annualized base salary of $425,000.

(7) | Such amount includes $75,000 in bonus pursuant to Mr. Key’s employment agreement.

(8) | Such amount includes $2,810 in the Company’s matching contributions under our 401(k) Savings and Investment Plan, and $7,290 in insurance premiums that we paid in respect of Mr. Keys.

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NARRATIVE DISCLOSURE TO SUMMARY COMPENSATION TABLE
Our Board and Compensation Committee review compensation for our Chief Executive Officer and other executive officers.
Our Board and Compensation Committee review compensation annually for our Chief Executive Officer and other executive officers. In setting executive base salaries and bonuses and granting equity incentive awards, the Compensation Committee and the Board consider compensation for comparable positions in the market, the historical compensation levels of our executives, individual performance as compared to our expectations and objectives, internal equity, our desire to motivate our employees to achieve short- and long-term results that are in the best interests of our stockholders, and a long-term commitment to our company. We target a general competitive position, based on independent third-party benchmark analytics to inform the mix of compensation of base salary, bonus and long-term incentives.
Our Compensation Committee is primarily responsible for determining the compensation for our executive officers. Our Compensation Committee typically reviews and discusses management’s proposed compensation with our Chief Executive Officer for all executives other than the chief executive officer. Based on those discussions and its discretion, taking into account the factors noted above, the Compensation Committee then sets the compensation for each executive officer other than the Chief Executive Officer and recommends the compensation for the Chief Executive Officer to our Board for approval, including base salaries and annual incentives and granting equity awards. Our Board discusses the Compensation Committee’s recommendation and ultimately approves the compensation of our Chief Executive Officer without members of management present. Our Compensation Committee has the authority to engage the services of a consulting firm or other outside advisor to assist it in designing our executive compensation programs and in making compensation decisions. In fiscal year 2021, prior to our initial public offering and the formation of our Compensation Committee, our management engaged Radford to provide executive and director compensation consulting services. Since our initial public offering and the establishment of our Compensation Committee, Radford has continued to serve as compensation consultant to management and the Compensation Committee.
Base Salaries
The base salary payable to each named executive officer is intended to provide a fixed component of compensation reflecting the executive’s skill set, experience, role and responsibilities. Effective upon the consummation of our initial public offering in July 2021, the 2021 annual base salaries for our named executive officers were $570,000 for Mr. Spignesi and $400,000 for Mr. Wirtjes. Mr. Keys employment began on October 1, 2021 and his 2021 annual base salary was $425,000 and, as a result, the amount shown in the “Salary” column of the Summary Compensation Table for 2021 reflects payments made to him from the period between October 1, 2021 and December 31, 2021. The 2021 annual base salaries for Messrs. Spignesi and Wirtjes and were $461,162 and $354,790, respectively, which were increased from their 2020 levels of $445,547 and $342,792, respectively.
Cash Incentive Compensation
We maintain an annual performance-based cash bonus program in which our named executive officers participated in 2021. Each named executive officer’s target bonus is expressed as a percentage of annual base salary, which can be achieved by meeting certain performance goals discussed below at target level. The 2021 annual bonuses for Messrs. Spignesi, Wirtjes and Keys were targeted at 80%, 50% and 50% of their base salaries, respectively.
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For the fiscal year ended December 31, 2021, our named executive officers were eligible to earn annual cash bonuses based on the achievement of certain corporate goals approved by the Board. In designing the performance goals for the 2021 bonus program, the Compensation Committee and Board considered the strategic goals of the Company and selected six performance metrics designed to align incentives and drive value creation for stockholders. The corporate goals under our 2021 bonus program related to the areas of: (i) commercial and revenue; (ii) new product development, (iii) gross margin improvement; (iv) profitability, cash flow and capitalization; (v) employees; and (vi) an initial public offering. Corporate achievement was weighted 125%. The following table details the weight, 2021 performance result and corresponding percentage earned for each performance metric:

Metric | ​ | ​ | Weight | ​ | ​ | 2021 Bonus Average Target Achieved | ​ | ​ | Earned Payout Percent
Commercial and Revenue Growth | ​ | ​ | 60% | ​ | ​ | 48.0% | ​ | ​ | 28.8%
New Product Development | ​ | ​ | 10% | ​ | ​ | 56.0% | ​ | ​ | 5.6%
Gross Margin Improvement | ​ | ​ | 10% | ​ | ​ | 7.7% | ​ | ​ | 0.8%
Financial | ​ | ​ | 10% | ​ | ​ | 97.1% | ​ | ​ | 9.7%
Create a “Best place to work” Environment | ​ | ​ | 10% | ​ | ​ | 50.0% | ​ | ​ | 5.0%
Initial Public Offering | ​ | ​ | 25% | ​ | ​ | 100.0% | ​ | ​ | 25.0%

In February 2022, the Compensation Committee met to review the Company’s performance against each of the metrics and determined final bonus amounts payable. The actual annual cash bonuses awarded to each named executive officer under the 2021 annual bonus program are set forth above in the Summary Compensation Table in the column entitled “Non-Equity Incentive Plan Compensation.”
Perquisites and Personal Benefits
We do not view perquisites or other personal benefits as a significant component of our executive compensation program. Accordingly, we do not provide perquisites or other personal benefits to our named executive officers, except as generally made available to our employees, or in situations where we believe it is appropriate to assist an individual in the performance of his or her duties, such as for recruitment purposes. In addition, our named executive officers are eligible to receive the same employee benefits that are generally available to all of our full-time employees, and do not receive additional health, welfare or retirement benefits.
Long-Term Equity Incentives
Although we do not have a formal policy with respect to the grant of equity incentive awards to our executive officers, we believe long-term equity incentive awards encourage retention, provide our executives with a strong link to our long-term performance, create an ownership culture, and help to align the interests of our executives and our stockholders. Accordingly, our Board and Compensation Committee, may grant stock options to our employees, including our named executive officers, in order to attract and retain them, as well as to align their interests with the interests of our stockholders.
In March 2021, we granted Mr. Spignesi an option to purchase 121,579 shares of our Class A common stock, and Mr. Wirtjes an option to purchase 24,360 shares of our Class A common stock. The options vest in 48 equal installments following March 9, 2021, subject to the executive’s continued service to us, provided that Mr. Spignesi’s option will vest in full in the event of a Change of Control, and the options granted to Mr. Wirtjes will vest in full in the event of such executive’s termination without Cause or resignation for Good Reason in connection with, and effective as of or within 12 months following, a Sale Event. These options were granted under our 2010 Stock Option and Grant Plan, which we refer to as the 2010 Plan, with exercise prices equal to the fair market value of our Class A common stock on the date of grant, as determined by the Board.
In connection with our initial public offering in July 2021, we adopted the 2021 Incentive Award Plan, referred to below as the 2021 Plan, to facilitate the grant of cash and equity incentives to directors, employees (including our named executive officers) and consultants of our company and certain of its affiliates and to enable us to obtain and retain services of these individuals, which is essential to our long-term success.
In October 2021, pursuant to his employment agreement, the Compensation Committee granted to Mr. Keys an option to purchase 180,000 shares of our Class A common stock which vests as to 25% of the shares subject to the option on October 1, 2022, with the remainder vesting in equal monthly installments for three years
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thereafter, subject to the executive’s continued service to us, provided that the options granted to Mr. Keys will vest in full in the event of such executive’s termination without Cause or resignation for Good Reason in connection with, and effective as of or within 12 months following, a Sale Event. These options were granted under our 2021 Plan, with an exercise price equal to the fair market value of our Class A common stock on the date of grant as defined under our 2021 Plan.
Outstanding Equity Awards at 2021 Fiscal Year-End
The following table summarizes the number of shares of Class A common stock underlying outstanding equity awards for each named executive officer as of December 31, 2021.

Name | ​ | ​ | Number of Securities Underlying Unexercised Options (#) Exercisable | ​ | ​ | Number of Securities Underlying Unexercised Options (#) Unexercisable | ​ | ​ | Option Exercise Price ($) | ​ | ​ | Option Expiration Date
Robert Spignesi | ​ | ​ | 4,210 | ​ | ​ | 0 | ​ | ​ | 0.75 | ​ | ​ | 10/22/2025
​ | 3,623 | ​ | ​ | 0 | ​ | ​ | 0.75 | ​ | ​ | 10/22/2025
​ | 3,400 | ​ | ​ | 0 | ​ | ​ | 0.75 | ​ | ​ | 10/22/2025
​ | 1,402 | ​ | ​ | 0 | ​ | ​ | 0.75 | ​ | ​ | 8/11/2026
​ | 174,964 | ​ | ​ | 0 | ​ | ​ | 1.00 | ​ | ​ | 10/11/2027
​ | 803,688 (1) | ​ | ​ | 73,063 | ​ | ​ | 1.00 | ​ | ​ | 5/28/2028
​ | 190,649 (2) | ​ | ​ | 347,656 | ​ | ​ | 0.75 | ​ | ​ | 7/28/2030
​ | 22,796 (3) | ​ | ​ | 98,783 | ​ | ​ | 10.85 | ​ | ​ | 3/14/2031
Sean Wirtjes | ​ | ​ | 51,020 (4) | ​ | ​ | 41,866 | ​ | ​ | 1.00 | ​ | ​ | 9/11/2028
​ | 26,965 (5) | ​ | ​ | 69,659 | ​ | ​ | 0.75 | ​ | ​ | 7/28/2030
​ | 4,567 (6) | ​ | ​ | 19,793 | ​ | ​ | 10.85 | ​ | ​ | 3/14/2031
Richard Keys | ​ | ​ | 0 (7) | ​ | ​ | 180,000 | ​ | ​ | 18.43 | ​ | ​ | 9/30/2031

(1) | The stock option has a vesting start date of April 12, 2018 and vest in 48 equal monthly installments following the vesting commencement date, subject to the executive’s continued service on each applicable vesting date, provided that the options will vest in full on a Change of Control.

(2) | The stock option has a vesting start date of July 29, 2020 and vests in 48 equal monthly installments following the vesting commencement date, subject to the executive’s continued service on each applicable vesting date, provided that the options will vest in full on a Change of Control.

(3) | The stock option has a vesting start date of March 9, 2021 and vests in 48 equal monthly installments following the vesting commencement date, subject to the executive’s continued service on each applicable vesting date, provided that the options will vest in full on a Change of Control.

(4) | The stock option has a vesting start date of September 12, 2018 and vests as to 25% of the underlying shares on the first anniversary of the vesting commencement date and as to 1/48th of the underlying shares on each monthly anniversary thereafter, subject to the executive’s continued service on each applicable vesting date, provided that the option will vest in full in the event of the executive’s termination without Cause or resignation for Good Reason in connection with, and effective as of or within 12 months following, a Sale Event.

(5) | The stock option has a vesting start date of July 29, 2020 and vests in 48 equal monthly installments following the vesting commencement date, subject to the executive’s continued service on each applicable vesting date, provided that the option will vest in full in the event of the executive’s termination without Cause or resignation for Good Reason in connection with, and effective as of or within 12 months following, a Sale Event.

(6) | The stock option has a vesting start date of March 9, 2021 and vests in 48 equal monthly installments following the vesting commencement date, subject to the executive’s continued service on each applicable vesting date, provided that the option will vest in full in the event of the executive’s termination without Cause or resignation for Good Reason in connection with, and effective as of or within 12 months following, a Sale Event.

(7) | The stock option has a vesting start date of October 1, 2021 and vests as to 25% of the underlying shares on the first anniversary of the vesting commencement date and as to 1/48th of the underlying shares on each monthly anniversary thereafter, subject to the executive’s continued service on each applicable vesting date, provided that the option will vest in full in the event of the executive’s termination without Cause or resignation for Good Reason in connection with, and effective as of or within 12 months following, a Sale Event.

Named Executive Officer Employment Agreements
Robert Spignesi
We entered into an employment agreement with Mr. Spignesi, effective as of July 14, 2021 (the “Spignesi Employment Agreement”). Pursuant to the Spignesi Employment Agreement, Mr. Spignesi receives a base salary
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of $570,000, which is subject to periodic review from time-to-time. Mr. Spignesi is also eligible to receive (i) an annual performance bonus targeted at 80% of his base salary, which may be adjusted from time to time, and (ii) to participate in the employee benefit plans generally available to our employees, subject to the terms of those plans.
Under the Spignesi Employment Agreement, if Mr. Spignesi is terminated by us without “cause” or if he resigns for “good reason” (each as defined in the Spignesi Employment Agreement), subject to his timely executing a release of claims and his continued compliance with certain restrictive covenants, Mr. Spignesi will be entitled to receive: (i) base salary continuation for a period of 12 months; (ii) payment of any earned but unpaid annual bonus for the year prior to the year of termination; (iii) an amount in cash equal to a pro-rated portion of the annual bonus for the year of termination based upon actual performance; (iv) continued health coverage pursuant to COBRA for up to 12 months following termination; and (v) (A) accelerated vesting of all unvested equity or equity-based awards held by Mr. Spignesi that vest solely based on continued employment or service and that would have vested during the six months following termination and (B) up to twelve months following the date of his termination to exercise any outstanding vested options.
In addition, if Mr. Spignesi is terminated by us without cause or if he resigns for good reason in either case, on or within three months prior to a change in control (as defined in the 2021 Plan), or within 12 months following a change in control, then, in lieu of the severance payments and benefits described above, subject to his timely executing a release of claims and the executive’s continued compliance with certain restrictive covenants, Mr. Spignesi is entitled to receive (i) a lump sum payment equal to 1.5 times his annual base salary; (ii) payment of any earned but unpaid annual bonus for the year prior to the year of termination; (iii) continued health coverage pursuant to COBRA for up to 18 months; (iv) a lump sum payment equal to 1.5 times his annual target bonus; and (v) full accelerated vesting of all unvested equity or equity-based awards and will have up to one year following the change in control to exercise any outstanding vested options.
Sean Wirtjes
We entered into an employment agreement with Mr. Wirtjes, effective as of July 14, 2021 (the “Wirtjes Employment Agreement”). Pursuant to the Wirtjes Employment Agreement, Mr. Wirtjes receives a base salary of $400,000, which is subject to periodic review from time to time. Mr. Wirtjes is also eligible to receive (i) an annual performance bonus targeted at 50% of his base salary, which may be adjusted from time to time, and (ii) to participate in the employee benefit plans generally available to our employees, subject to the terms of those plans.
Under the Wirtjes Employment Agreement, if Mr. Wirtjes is terminated by us without “cause” or if he resigns for “good reason” (each as defined in the Wirtjes Employment Agreement), subject to his timely executing a release of claims and his continued compliance with certain restrictive covenants, Mr. Wirtjes will be entitled to receive: (i) base salary continuation equal to 75% of his base salary; (ii) payment of any earned but unpaid annual bonus for the year prior to the year of termination; (iii) an amount in cash equal to a pro-rated portion of the annual bonus for the year of termination based upon actual performance; and (iv) continued health coverage pursuant to COBRA for up to nine months following termination.
In addition, if Mr. Wirtjes is terminated by us without cause or if he resigns for good reason in either case, on or within three months prior to a change in control, or within 12 months following a change in control, then, in lieu of the severance payments and benefits described above, subject to his timely executing a release of claims and the executive’s continued compliance with certain restrictive covenants, Mr. Wirtjes is entitled to receive (i) a lump sum payment equal to one times his annual base salary; (ii) payment of any earned but unpaid annual bonus for the year prior to the year of termination; (iii) continued health coverage pursuant to COBRA for up to 12 months; (iv) a lump sum payment equal to one times his annual target bonus; and (v) full accelerated vesting of all unvested equity or equity-based awards held by him that vest solely based on continued employment or service.
Richard Keys
We entered into an employment agreement with Richard Keys, effective October 1, 2021 (the “Keys Employment Agreement”). Pursuant to the Keys Employment Agreement, Mr. Keys receives a base salary of $425,000, which is subject to review from time to time, and a one-time sign-on bonus in the amount of $75,000. Mr. Keys is also eligible (i) to receive an annual performance bonus targeted at 50% of his base salary, which
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may be adjusted from time to time, (ii) annual commission in the amount of $7,000 for every 1% above 100% of the total revenue which the Company exceeds, with a maximum annual commission cap in the amount of $175,000, and (iii) to participate in the employee benefit plans generally available to our employees, subject to the terms of those plans.
Under the Keys Employment Agreements, if Mr. Keys is terminated by us without “cause” or if he resigns for “good reason” (each as defined in the Keys Employment Agreement), subject to his timely executing a release of claims and his continued compliance with certain restrictive covenants, Mr. Keys will be entitled to receive: (i) base salary continuation equal to 75% of his base salary; (ii) payment of any earned but unpaid annual bonus for the year prior to the year of termination; (iii) an amount in cash equal to a pro-rated portion of the annual bonus for the year of termination based upon actual performance; and (iv) continued health coverage pursuant to COBRA for up to nine months following termination.
In addition, if Mr. Keys is terminated by us without cause or he resigns for good reason, in either case, on or within three months prior to a change in control, or within 12 months following a change in control, then, in lieu of the severance payments and benefits described above, subject to his timely executing a release of claims and his continued compliance with certain restrictive covenants, such executive is entitled to receive (i) a lump sum payment equal to one times his annual base salary; (ii) payment of any earned but unpaid annual bonus for the year prior to the year of termination; (iii) continued health coverage pursuant to COBRA for up to 12 months following termination ; (iv) a lump sum payment equal to one times his annual target bonus; and (v) full accelerated vesting of all unvested equity or equity-based awards held by him that vest solely based on continued employment or service.
Each of our named executive officers has agreed to refrain from competing with us while employed and for a period of 12 months following his or her termination of employment if terminated for cause or if the executive resigns for any reason and as a condition to the receipt of severance benefits upon a termination without cause or resignation for good reason. Each of our named executive officers has also agreed to refrain from soliciting our employees, consultants, customers, suppliers or vendors, in each case, while employed and for a period of 12 months following his or her termination of employment for any reason.
Other Elements of Compensation
Retirement Plans
We currently maintain a 401(k) retirement savings plan for our employees, including our named executive officers, who satisfy certain eligibility requirements. Our named executive officers are eligible to participate in the 401(k) plan on the same terms as other full-time employees. The Internal Revenue Code of 1986, as amended, or the Code, allows eligible employees to defer a portion of their compensation, within prescribed limits, on a pre-tax basis through elective contributions to the 401(k) plan. Through December 31, 2021, we matched contributions made by participants in the 401(k) plan up to a specified percentage of the employee contributions, and these matching contributions are fully vested as of the date on which the contribution is made. Commencing January 1, 2022, the Compensation Committee established an employer discretionary matching contribution under the 401k Plan equal to one hundred percent (100%) on the first two percent (2%) of participant’s eligible contributed compensation and fifty percent (50%) on the next four percent (4%) of the participant’s eligible contributed compensation, with such employer discretionary matching contributions subject to vesting service requirements. We believe that providing a vehicle for tax-deferred retirement savings though our 401(k) plan adds to the overall desirability of our executive compensation package and further incentivizes our employees, including our named executive officers, in accordance with our compensation policies.
Employee Benefits
All of our full-time employees, including our named executive officers, are eligible to participate in our health and welfare plans, which for U.S. employees include medical, dental and vision benefits, medical and dependent care flexible spending accounts, short-term and long-term disability insurance, and life insurance, on the same terms.
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EQUITY COMPENSATION PLAN INFORMATION
The following table provides information as of December 31, 2021, with respect to the securities authorized for issuance under our equity compensation plans, consisting of:

• | 2010 Stock Option and Grant Plan

• | 2021 Incentive Award Plan

• | 2021 Employee Stock Purchase Plan

Plan Category | ​ | ​ | Number of Securities to be Issued Upon Exercise of Outstanding Options, Warrants and Rights | ​ | ​ | Weighted Average Exercise Price of Outstanding Options, Warrants and Rights | ​ | ​ | Number of Securities Available for Future Issuance Under Equity Compensation Plans
Equity compensation plans approved by security holders(1) | ​ | ​ | 4,823,100 | ​ | ​ | $5.06 | ​ | ​ | 4,174,298(2)(3)
Equity compensation plans not approved by security holders | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Total | ​ | ​ | 4,823,100 | ​ | ​ | $5.06 | ​ | ​ | 4,174,298

(1) | Includes securities issuable upon rights that were granted pursuant to our 2010 Plan. No additional awards will be granted under this plan. Additionally, balance includes securities issuable upon rights that have been issued pursuant to the 2021 Plan, which is currently available for future grants.

(2) | Our 2021 Plan provides that a number of shares initially available for issuance will automatically increase on January 1 of each calendar year beginning in 2022 and ending in and including 2031, equal to the lesser of (A) 5% of the shares of Class A common stock outstanding on the final day of the immediately preceding calendar year and (B) a smaller number of shares determined by our board of directors. On January 1, 2022, the number of shares available for issuance increased automatically by 1,728,202 shares, pursuant to this provision. This increase is not reflected in the table above. In addition, the number of shares available for issuance under the 2021 Employee Stock Purchase Plan (the “2021 ESPP”) will be annually increased on January 1 of each calendar year beginning in 2022 and ending in and including 2031, by an amount equal to the lesser of (A) 1% of the shares outstanding on the final day of the immediately preceding calendar year and (B) such smaller number of shares as is determined by our board of directors, provided that no more than 6,300,000 shares of our Class A common stock may be issued under the 2021 ESPP. On January 1, 2022, the number of shares available for issuance under the 2021 ESPP increased automatically by 345,640 shares pursuant to this provision. This increase is not reflected in the table above.

(3) | As of December 31, 2021, there were 3,774,298 shares available for grant under the 2021 Plan and 400,000 shares available for grants under the 2021 ESPP.

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PART 5 – AUDIT COMMITTEE MATTERS
Report of the Audit Committee of the Board of Directors
Our Audit Committee was established in July 2021 and was initially comprised of Melinda Litherland, Richard Kollender and Alexander Schmitz. The most recently amended Audit Committee Charter is available in the Corporate Governance section of our web site, investors.rapidmicrobio.com.
The Audit Committee has reviewed Rapid Micro Biosystems’ audited consolidated financial statements for the fiscal year ended December 31, 2021 and has discussed these financial statements with management and Rapid Micro Biosystems’ independent registered public accounting firm. The Audit Committee has also received from, and discussed with, Rapid Micro Biosystems’ independent registered public accounting firm the matters that they are required to provide to the Audit Committee, including the matters required to be discussed by the Public Company Accounting Oversight Board (“PCAOB”) and the Securities and Exchange Commission (“SEC”).
Rapid Micro Biosystems’ independent registered public accounting firm also provided the Audit Committee with a formal written statement required by PCAOB Rule 3526 (Communications with Audit Committees Concerning Independence) describing all relationships between the independent registered public accounting firm and Rapid Micro Biosystems, including the disclosures required by the applicable requirements of the PCAOB regarding the independent registered public accounting firm’s communications with the Audit Committee concerning independence. In addition, the Audit Committee discussed with the independent registered public accounting firm its independence from Rapid Micro Biosystems.
Based on its discussions with management and the independent registered public accounting firm, and its review of the representations and information provided by management and the independent registered public accounting firm, the Audit Committee recommended to the Board that the audited consolidated financial statements be included in our 2021 Annual Report on Form 10-K for the fiscal year ended December 31, 2021 that was filed with the SEC.
Melinda Litherland (Chairperson)
Richard Kollender
Inese Lowenstein
Alexander Schmitz
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Independent Registered Public Accounting Firm Fees and Other Matters
Set forth below are the fees paid to our independent registered public accounting firm, PricewaterhouseCoopers LLP, for the fiscal years ended December 31, 2021 and 2020 (in thousands):

Fee Category | ​ | ​ | Fiscal Year 2021 | ​ | ​ | Fiscal Year 2020
Audit Fees | ​ | ​ | $2,235 | ​ | ​ | $635
Audit-Related Fees | ​ | ​ | $0 | ​ | ​ | $0
Tax Fees | ​ | ​ | $180 | ​ | ​ | $112
All Other Fees | ​ | ​ | $3 | ​ | ​ | $3
Total Fees | ​ | ​ | $2,418 | ​ | ​ | $750

AUDIT FEES
Audit fees consist of fees for the audit of our consolidated financial statements, the review of the unaudited interim financial statements included in our quarterly reports on Form 10-Q and other professional services provided in connection with statutory and regulatory filings or engagements. Audit fees in fiscal year 2021 also includes fees for professional services incurred by us in connection with our initial public offering. Audit fees for fiscal year 2020 also include professional services rendered in connection with the original 2020 audit and 2019 PCAOB uplift procedures.
AUDIT-RELATED FEES
Audit-related fees consist of fees billed for assurance and related services that are reasonably related to the performance of the audit or review of our consolidated financial statements, and are not reported under Audit Fees. For fiscal years 2021 and 2020, there were no Audit-Related Fees incurred for professional services.
TAX FEES
Tax fees consist of fees for a variety of permissible services relating to domestic and international tax advisory and compliance services.
ALL OTHER FEES
All other fees consist of fees and related expenses for products and services other than services described above, including fees to the independent registered public accounting firm or its affiliates for annual subscriptions to online accounting and tax research software applications and data.
AUDIT COMMITTEE PRE-APPROVAL POLICY AND PROCEDURES
Our Audit Committee’s charter provides that the Audit Committee, or the chair of the Audit Committee, must pre-approve any audit or non-audit service provided to us by our independent registered public accounting firm, unless the engagement is entered into pursuant to appropriate pre-approval policies established by the Audit Committee or if the service falls within available exceptions under SEC rules. Without limiting the foregoing, the Audit Committee may delegate authority to one or more independent members of the Audit Committee to grant pre-approvals of audit and permitted non-audit services, and any such pre-approvals must be presented to the full Audit Committee at its next scheduled meeting. All services provided by our independent registered public accounting firm following our initial public offering in 2021 were approved in accordance with such pre-approval policies and consistent with SEC rules.
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PART 6 - SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT
The following table sets forth information with respect to the beneficial ownership of our common stock, as of March 31, 2022 by:

• | each person or group of affiliated persons known by us to beneficially own more than 5% of our common stock;

• | each of our named executive officers;

• | each of our directors; and

• | all of our executive officers and directors as a group.

The number of shares beneficially owned by each stockholder is determined under rules issued by the Securities and Exchange Commission. Under these rules, beneficial ownership includes any shares as to which the individual or entity has sole or shared voting power or investment power. Applicable percentage ownership is based on 36,386,948 shares of Class A common stock. In computing the number of shares beneficially owned by an individual or entity and the percentage ownership of that person, shares of common stock subject to options, warrants or other rights held by such person that are currently exercisable or will become exercisable within 60 days of March 31, 2022 are considered outstanding, although these shares are not considered outstanding for purposes of computing the percentage ownership of any other person. As of March 31, 2022, we also have 5,553,379 shares of Class B common stock outstanding. We shall not effect any conversion of our Class B common stock, and a holder of our Class B common stock shall not have the right to convert any portion of such holder's Class B Common Stock, to the extent that, after giving effect to such conversion, such holder would beneficially own in excess of 4.9% of the total number of shares of our Class A common stock then issued and outstanding (the “Beneficial Ownership Limitation”). As a result, the shares of Class A common stock issuable upon the conversion of Class B common stock held by certain shareholders are not convertible within 60 days of March 31, 2022 by virtue of the Beneficial Ownership Limitation and are not reflected on the table below. Unless noted otherwise, the address of all listed stockholders is 1001 Pawtucket Boulevard West, Suite 280, Lowell, Massachusetts 01854. Each of the stockholders listed has sole voting and investment power with respect to the shares beneficially owned by the stockholder unless noted otherwise, subject to community property laws where applicable.
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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

| ​ | ​ | Shares of Class A Common Stock Beneficially Owned
Name of beneficial owner | ​ | ​ | Number | ​ | ​ | Percentage
Major Stockholders Including 5% or Greater Stockholders | ​ | ​ |  | ​ | ​ |
Entities affiliated with Bain Capital Life Sciences Investors, LLC(1) | ​ | ​ | 8,434,560 | ​ | ​ | 23.18%
Entities affiliated with Longitude Capital Partners II, LLC(2) | ​ | ​ | 4,189,845 | ​ | ​ | 11.32%
D1 Master Holdco I LLC(3) | ​ | ​ | 2,644,444 | ​ | ​ | 7.27%
Entities affiliated with Endeavour Medtech Growth II LP(4) | ​ | ​ | 2,243,635 | ​ | ​ | 6.17%
T. Rowe Price Associates, Inc.(5) | ​ | ​ | 2,199,746 | ​ | ​ | 6.05%
Colony Harvest Ltd.(6) | ​ | ​ | 2,084,273 | ​ | ​ | 5.73%
| ​ | ​ |  | ​ | ​ |
Named Executive Officers and Directors | ​ | ​ |  | ​ | ​ |
Robert Spignesi(7) | ​ | ​ | 1,409,163 | ​ | ​ | 3.87%
Sean Wirtjes(8) | ​ | ​ | 266,215 | ​ | ​ | *
Richard Keys(9) | ​ | ​ | 5,468 | ​ | ​ | *
David Hirsch, M.D., Ph.D.(10) | ​ | ​ | 4,196,789 | ​ | ​ | 11.34%
Richard Kollender(11) | ​ | ​ | 188,474 | ​ | ​ | *
Melinda Litherland(12) | ​ | ​ | 6,944 | ​ | ​ | *
Inese Lowenstein(13) | ​ | ​ | 13,472 | ​ | ​ | *
Natale Ricciardi(14) | ​ | ​ | 66,986 | ​ | ​ | *
Alexander Schmitz(15) | ​ | ​ | 6,944 | ​ | ​ | *
Jeffrey Schwartz(16) | ​ | ​ | 8,441,504 | ​ | ​ | 23.20%
All executive officers and directors as a group(17) (13 persons) | ​ | ​ | 14,822,903 | ​ | ​ | 38.04%

* | Represents beneficial ownership of less than 1%.

(1) | With respect to entities affiliated with Bain Capital Life Sciences Investors, LLC (“BCLSI”), we have relied solely on information supplied by such entity on a Schedule 13G filed with the SEC on February 14, 2022. Consists of (i) 7,651,369 shares of Class A common stock held by Bain Capital Life Sciences Fund, L.P. (“BCLS”) and (ii) 783,191 shares of Class A common stock held by BCIP Life Sciences Associates, LP (“BCIPLS” and together with BCLS, the “Bain Capital Life Sciences Entities”). BCLSI is the ultimate general partner of BCLS and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. Jeffrey Schwartz, the chairman of our Board, and Adam Koppel are managers of BCLSI. As a result, BCLSI, Mr. Schwartz and Dr. Koppel may each be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. The business address of the each of the entities and individuals above is 200 Clarendon Street, Boston, Massachusetts 02116.

(2) | With respect to entities affiliated with Longitude Venture Partners II, L.P. (“LVPII”), we have relied solely on information supplied by such entity on a Schedule 13G filed with the SEC on February 15, 2022. Consists of (i) 3,407,952 shares of Class A common stock held by LVPII, (ii) 150,000 shares of Class A common stock held by Longitude Prime Fund, L.P. (“LPF” and together with LVPII, the “Longitude Entities”) and (iii) 631,893 shares of Class A common stock issuable upon the conversion of warrants exercisable within 60 days of March 31, 2022 held by LVPII. Longitude Capital Partners II, LLC (“LCPII”) is the general partner of LVPII and may be deemed to have voting and investment power over the shares held by LVPII. Patrick G. Enright and Juliet Tammenoms Bakker are managing members of LCPII and may be deemed to share voting and investment power over the shares held by LVPII. David Hirsch, one of our directors, is a member of LCPII and may be deemed to share voting and investment power over the shares held by LVPII. As general partner of LPF, Longitude Prime Partners, LLC (“LPP”) may be deemed to beneficially own the shares held by LPF. Mr. Enright and Ms. Tammenoms Bakker are the managing members of LPP and may be deemed to share voting, investment and dispositive power with respect to the shares held by LPF. LCPII, LPP, Mr. Enright, Ms. Tammenoms Bakker and Dr. Hirsch each disclaim beneficial ownership of such shares except to the extent of their respective pecuniary interest therein. The mailing address for each of the entities and individuals above is 2740 Sand Hill Road, Menlo Park, California 94025.

(3) | With respect to D1 Master Holdco I LLC (“D1 Holdco”), we have relied solely on information supplied by such entity on a Schedule 13G filed with the SEC on February 14, 2022. Consists of 2,644,444 shares of Class A common stock held by D1 Holdco. D1 Capital Partners L.P. (“D1 Investment Manager”) is a registered investment adviser and serves as the manager of private investment vehicles and accounts, including D1 Capital Partners Master LP (“D1 Investment Vehicle”), the sole and managing member of D1 Holdco, and may be deemed to beneficially own the shares of common stock held by D1 Holdco. Daniel Sundheim indirectly controls the D1 Investment Manager and may be deemed to beneficially own the shares held by D1 Holdco. The business address of each of each of the entities and individuals above is 9 West 57th Street, 36th Floor, New York, New York 10019.

(4) | With respect to entities affiliated with Endeavour Medtech Growth II LP (“Endeavour Growth”), we have relied solely on information supplied by such entities on a Schedule 13G/A filed with the SEC on February 2, 2022. Consists of (i) 2,203,965 shares of Class A common stock held by Endeavour Growth, and (ii) 39,670 shares of Class A common stock held by Endeavour Medtech Growth Parallel II LP (“Endeavour Parallel”). The general partner of Endeavour Growth and Endeavour Parallel is Endeavour Medtech II GP

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Limited (“Endeavour GP”). Endeavour GP is controlled by a board of three directors that acts by majority approval and possesses sole voting and dispositive power with respect to the shares held by Endeavour Growth and Endeavour Parallel. The individual members of such board are: John Bridle, Nick Barton and Michel Davy. Each of Messrs. Bridle, Barton and Davy disclaim beneficial ownership of the shares held by Endeavour Growth and Endeavour Parallel except to the extent of his pecuniary interest therein. The mailing address for each of the entities and individuals above is c/o Endeavour Medtech Growth II LP, P.O. Box 656, East Wing Trafalgar Court, Les Banques, St Peter Port, Guernsey GY1 3PP.

(5) | With respect to information relating to T. Rowe Price Associates, Inc. (“Price Associates”), we have relied solely on information supplied by such entity on a Schedule 13G filed with the SEC on February 14, 2022. Consists of 2,199,746 shares of Class A common stock held by Price Associates. The Schedule 13G discloses that Price Associates has sole voting power over 488,279 shares and sole dispositive power over 2,199,746 shares. Price Associates does not serve as custodian of the assets of any of its clients; accordingly, in each instance only the client or the client’s custodian or trustee bank has the right to receive dividends paid with respect to, and proceeds from the sale of, such securities. The ultimate power to direct the receipt of dividends paid with respect to, and the proceeds from the sale of, such securities, is vested in the individual and institutional clients which Price Associates serves as investment adviser. Any and all discretionary authority which has been delegated to Price Associates may be revoked in whole or in part at any time. The mailing address for Price Associates is 100 E. Pratt Street, Baltimore, Maryland 21202.

(6) | With respect to information relating to Colony Harvest Ltd. (“Colony Harvest”), we have relied solely on information supplied by such entity in a Schedule 13G filed on February 11, 2022. Consists of 2,084,273 shares of Class A common stock held by Colony Harvest. Colony Harvest is the Special Purpose Vehicle set up by Xeraya Capital (“Xeraya”) for investment into the Company. Xeraya may be deemed to be the beneficial owners of shares held by Colony Harvest. Fares Zahir is the director of Colony Harvest and may be deemed to be the beneficial owner of the shares held by Colony Harvest. Mr. Zahir disclaims beneficial ownership except to the extent of his pecuniary interest therein. Bruce Cohen, a former member of our board, is a Venture Partner at Xeraya. Mr. Cohen may be deemed to beneficially own the shares held by Colony Harvest and disclaims beneficial ownership except to the extent of his pecuniary interest therein. The mailing address for Colony Harvest is 26.03-26.08, Level 26 G Tower, No. 199, Jalan Tun Razak, 50400 Kuala Lumpur, Malaysia.

(7) | Includes (i) 85,277 shares of Class A common stock, (ii) 10 shares of Class A common stock issuable upon the conversion of warrants exercisable within 60 days of March 31, 2022 and (iii) 1,323,876 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Mr. Spignesi.

(8) | Includes (i) 151,631 shares of Class A common stock and (ii) 114,584 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Mr. Wirtjes.

(9) | Includes 5,468 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Mr. Keys.

(10) | Consists of (i) 6,944 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Dr. Hirsch and (ii) the shares described in note (2) above. Dr. Hirsch is a member of LCPII and may be deemed to share voting and investment power over the shares held by LVPII.

(11) | Includes 188,474 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Mr. Kollender. Mr. Kollender is an executive manager of Quaker Partners Management, LP (“Quaker”). Mr. Kollender has no voting and investment power over the securities held by Quaker and disclaims beneficial ownership of the securities held by Quaker except to the extent of any pecuniary interest therein.

(12) | Includes 6,944 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Ms. Litherland.

(13) | Includes (i) 10,000 shares of Class A common stock and (ii) 3,472 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Ms. Lowenstein.

(14) | Includes 66,986 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Mr. Ricciardi.

(15) | Includes 6,944 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Mr. Schmitz.

(16) | Consists of (i) 6,944 shares of Class A common stock underlying options exercisable within 60 days of March 31, 2022 held by Mr. Schwartz and (ii) the shares described in note (1) above. Mr. Schwartz is a manager of BCLSI, which is the ultimate general partner of BCLS and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, Mr. Schwartz may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities.

(17) | Includes (i) 12,239,420 shares of Class A common stock, (ii) 631,903 shares of Class A common stock issuable upon the conversion of warrants exercisable within 60 days of March 31, 2022 and (iii) 1,951,580 options which are exercisable within 60 days of March 31, 2022.

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CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS
The following includes a summary of transactions since January 1, 2020 to which we have been a party in which the amount involved exceeded or will exceed the lesser of (i) $120,000 or (ii) one percent of the average of our total assets at fiscal year-end for our last two fiscal years, and in which any of our directors, executive officers or, to our knowledge, beneficial owners of more than 5% of our capital stock or any member of the immediate family of any of the foregoing persons had or will have a direct or indirect material interest. We also describe below certain other transactions with our directors, executive officers and stockholders.
PREFERRED STOCK FINANCINGS
Series C1/C2 Preferred Stock Financing. In April 2020, we issued and sold to investors in a private placement an aggregate of (i) 23,611,208 shares of our Series C1 preferred stock at a purchase price of $1.15 per share, (ii) 10,351,063 shares of Series C1 preferred stock in connection with the conversion of convertible promissory notes at a conversion price of $1.087 per share, and (iii) 20,301,829 shares of our Series C2 preferred stock at a purchase price of $1.15 per share, for aggregate consideration of approximately $60.0 million.
Series D1/D2 Preferred Stock Financing. In March 2021, we issued and sold to investors in a private placement an aggregate of 22,086,725 shares of our Series D1 preferred stock and an aggregate of 413,268 shares of our Series D2 preferred stock at a purchase price of $3.60 per share, for aggregate consideration of approximately $81.0 million.
The following table sets forth the aggregate number of shares of our capital stock acquired by beneficial owners of more than 5% of our capital stock in the financing transactions described above. Each share of our Series B1 preferred stock, Series C1 preferred stock, and Series D1 preferred stock converted into 0.2 of a share of Class A common stock immediately prior to the closing of our initial public offering. Each share of our Series C2 preferred stock and Series D2 preferred stock converted into 0.2 of a share of Class B common stock immediately prior to the closing of our initial public offering.

Participants | ​ | ​ | Series C1 Preferred Stock | ​ | ​ | Series C2 Preferred Stock | ​ | ​ | Series D1 Preferred Stock | ​ | ​ | Series D2 Preferred Stock
5% or Greater Stockholders(1) | ​ | ​ |  | ​ | ​ |  | ​ | ​ |  | ​ | ​ |
Bain Capital Life Sciences Fund, L.P. | ​ | ​ | 6,053,214 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
ABG WTT-Rapid Limited | ​ | ​ | — | ​ | ​ | 31,739,130 | ​ | ​ | — | ​ | ​ | —
Ally Bridge MedAlpha Master Fund L.P. | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 2,777,777
Longitude Venture Partners II, L.P. | ​ | ​ | 2,291,665 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Colony Harvest Ltd. | ​ | ​ | 2,382,682 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Endeavour Medtech Growth II LP | ​ | ​ | 8,828,422 | ​ | ​ | — | ​ | ​ | 1,388,888 | ​ | ​ | —

(1) | Additional details regarding these stockholders and their equity holdings are provided in this proxy statement under the section titled “Security Ownership of Certain Beneficial Owners and Management.”

Some of our directors are associated with our principal stockholders as indicated in the table below:

Director | ​ | ​ | Principal Stockholder
Bruce Cohen(1) | ​ | ​ | Colony Harvest Ltd.
Jeffrey Schwartz | ​ | ​ | Bain Capital Life Sciences Fund, L.P.
David Hirsch, M.D., Ph.D. | ​ | ​ | Longitude Venture Partners II, L.P.
Alexander Schmitz | ​ | ​ | Endeavour Medtech Growth II LP

(1) | Mr. Cohen resigned from our Board effective July 14, 2021.

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INITIAL PUBLIC OFFERING
In July 2021, in connection with our initial public offering, we sold an aggregate of 7,290,000 shares of our Class A common stock at a public offering price of $20.00 per share. In August 2021, the underwriters exercised their overallotment option in part and purchased 1,086,604 shares of our Class A common stock at the initial public offering price of $20.00 per share. The aggregate gross proceeds to us from the initial public offering were approximately $178.6 million, before deducting underwriting discounts and commissions and other offering expenses. The following table summarizes purchases of our shares of common stock by related persons in connection with our initial public offering:

STOCKHOLDER(1) | ​ | ​ | SHARES OF CLASS A COMMON STOCK | ​ | ​ | TOTAL PURCHASE PRICE
Bain Capital Life Sciences Fund, L.P. | ​ | ​ | 100,000 | ​ | ​ | $2,000,000
Longitude Venture Partners II, L.P. | ​ | ​ | 150,000 | ​ | ​ | $3,000,000
Endeavour Medtech Growth II LP | ​ | ​ | 200,000 | ​ | ​ | $4,000,000

(1) | Additional details regarding these stockholders and their equity holdings are provided in this proxy statement under the section titled “Security Ownership of Certain Beneficial Owners and Management.”

EXCHANGE AGREEMENT
In June 2021, we entered into an exchange agreement with ABG WTT and Ally Bridge MedAlpha, pursuant to which we issued to ABG WTT 11,437,301 shares of our Series C2 preferred stock in exchange for an equal number of shares of Series C1 preferred stock and 2,364,509 shares of Series D2 preferred stock in exchange for an equal number of shares of Series D1 preferred stock.
INVESTOR RIGHTS AGREEMENT
We entered into a Seventh Amended and Restated Investors’ Rights Agreement in March 2021 with the holders of our preferred stock, including entities with which certain of our directors are related. The agreement provides for certain rights relating to the registration of such holders’ common stock, including shares issuable upon conversion of preferred stock, and a right of first refusal to purchase future securities sold by us.
VOTING AGREEMENT
We entered into a Seventh Amended and Restated Voting Agreement by and among us and certain of our stockholders, pursuant to which the following directors were elected to serve as members on our Board and, as of the date of this proxy statement, continue to so serve: Robert Spignesi, Richard Kollender, Jeffrey Schwartz, Natale Ricciardi, David Hirsch and Alexander Schmitz. Robert Spignesi was selected to serve on our Board in his capacity as our chief executive officer. Jeffrey Schwartz, David Hirsch and Alexander Schmitz were initially selected to serve on our Board as representatives of holders of our preferred stock, as designated by entities affiliated with Bain Capital Life Sciences Fund, L.P., Longitude Venture Partners II, L.P. and Endeavour Medtech Growth II LP, respectively.
The voting agreement terminated upon the closing of our initial public offering, and members previously elected to our Board pursuant to this agreement will continue to serve as directors until they resign, are removed or their successors are duly elected by the holders of our common stock.
INDEMNIFICATION AGREEMENTS
In connection with our initial public offering, we entered into indemnification agreements with each of our directors and executive officers. These agreements, among other things, require us to indemnify each director (and in certain cases their related venture capital funds) and executive officer to the fullest extent permitted by Delaware law, including indemnification of expenses such as attorneys’ fees, judgments, fines and settlement amounts incurred by the director or executive officer in any action or proceeding, including any action or proceeding by or in right of us, arising out of the person’s services as a director or executive officer.
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POLICIES AND PROCEDURES FOR RELATED PERSON TRANSACTIONS
Our Board has adopted a written related person transaction policy setting forth the policies and procedures for the review and approval or ratification of related person transactions. This policy covers, with certain exceptions set forth in Item 404 of Regulation S-K under the Securities Act, any transaction, arrangement or relationship, or any series of similar transactions, arrangements or relationships, in which we were or are to be a participant, where the amount involved exceeds the lesser of (i) $120,000 or (ii) one percent of the average of our total assets at fiscal year-end for any fiscal year and a related person had, has or will have a direct or indirect material interest, including without limitation, purchases of goods or services by or from the related person or entities in which the related person has a material interest, indebtedness, guarantees of indebtedness and employment by us of a related person. In reviewing and approving any such transactions, our audit committee is tasked to consider all relevant facts and circumstances, including, but not limited to, whether the transaction is on terms comparable to those that could be obtained in an arm’s length transaction and the extent of the related person’s interest in the transaction. All of the transactions described in this section occurred prior to the adoption of this policy.
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PART 7 - OTHER MATTERS
COMPENSATION COMMITTEE INTERLOCKS AND INSIDER PARTICIPATION
No member of our compensation committee is or has been our current or former officer or employee. None of our executive officers served as a director or a member of a compensation committee (or other committee serving an equivalent function) of any other entity, one of whose executive officers served as a director or member of our compensation committee during the fiscal year ended December 31, 2021.
STOCKHOLDERS’ PROPOSALS
Stockholders who intend to have a proposal considered for inclusion in our proxy materials for presentation at our 2023 Annual Meeting of Stockholders pursuant to Rule 14a-8 under the Exchange Act must submit the proposal to our Secretary at our offices at 1001 Pawtucket Boulevard West, Suite 280, Lowell, Massachusetts 01854 in writing not later than December 9, 2022, the date that is 120 days prior to the first anniversary of the date of this proxy statement, in order to be included in the proxy statement and proxy card relating to that meeting.
Stockholders intending to present a proposal at the 2023 Annual Meeting of Stockholders, but not to include the proposal in our proxy statement, or to nominate a person for election as a director, must comply with the requirements set forth in our amended and restated bylaws. Our amended and restated bylaws require, among other things, that our Secretary receive written notice from the stockholder of record of their intent to present such proposal or nomination not earlier than the close of business on the 120th day and not later than the close of business on the 90th day prior to the first anniversary of the preceding year’s annual meeting. Therefore, we must receive notice of such a proposal or nomination for the 2023 Annual Meeting of Stockholders no earlier than the close of business on January 23, 2023 and no later than the close of business on February 22, 2023. The notice must contain the information required by the Amended and Restated Bylaws, a copy of which is available upon request to our Secretary. In the event that the date of the 2023 Annual Meeting of Stockholders is more than 30 days before or more than 60 days after May 23, 2023, then our Secretary must receive such written notice not earlier than the close of business on the 120th day prior to the 2023 Annual Meeting of Stockholders and not later than the close of business on the 90th day prior to the 2023 Annual Meeting of Stockholders or, if later, the 10th day following the day on which public disclosure of the date of such meeting is first made by us. SEC rules permit management to vote proxies in its discretion in certain cases if the stockholder does not comply with this deadline and, in certain other cases notwithstanding the stockholder’s compliance with this deadline.
To comply with the universal proxy rules (once effective), stockholders who intend to solicit proxies in support of director nominees other than the Company’s nominees for the 2023 Annual Meeting of Stockholders must provide notice that sets forth the information required by Rule 14a-19 under the Exchange Act no later than 60 days prior to the first anniversary of the 2022 Annual Meeting.
We reserve the right to reject, rule out of order, or take other appropriate action with respect to any proposal that does not comply with these or other applicable requirements.
OTHER MATTERS AT THE ANNUAL MEETING
Our Board is not aware of any matter to be presented for action at the Annual Meeting other than the matters referred to above and does not intend to bring any other matters before the Annual Meeting. However, if other matters should come before the Annual Meeting, it is intended that holders of the proxies will vote thereon in their discretion.
SOLICITATION OF PROXIES
The accompanying proxy is solicited by and on behalf of our Board, whose Notice of Annual Meeting is attached to this proxy statement, and the entire cost of our solicitation will be borne by us. In addition to the use of mail, proxies may be solicited by personal interview, telephone, e-mail and facsimile by our directors, officers and other employees who will not be specially compensated for these services. We will also request that brokers, nominees, custodians and other fiduciaries forward soliciting materials to the beneficial owners of shares held by the brokers, nominees, custodians and other fiduciaries. We will reimburse these persons for their reasonable expenses in connection with these activities.
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RAPID MICRO BIOSYSTEMS’ ANNUAL REPORT ON FORM 10-K
A copy of Rapid Micro Biosystems’ Annual Report on Form 10-K for the fiscal year ended December 31, 2021, including financial statements and schedules but not including exhibits, as filed with the SEC, will be sent to any stockholder of record on March 31, 2022 without charge upon written request addressed to:
Rapid Micro Biosystems, Inc.
Attention: Secretary
1001 Pawtucket Boulevard West, Suite 280
Lowell, Massachusetts 01854
A reasonable fee will be charged for copies of exhibits. You also may access this proxy statement and our Annual Report on Form 10-K at www.proxyvote.com. You also may access our Annual Report on Form 10-K for the fiscal year ended December 31, 2021 at investors.rapidmicrobio.com.
WHETHER OR NOT YOU PLAN TO ATTEND THE ANNUAL MEETING, WE URGE YOU TO VOTE YOUR SHARES VIA THE TOLL-FREE TELEPHONE NUMBER OR OVER THE INTERNET, AS DESCRIBED IN THIS PROXY STATEMENT. IF YOU RECEIVED A COPY OF THE PROXY CARD BY MAIL, YOU MAY SIGN, DATE AND MAIL THE PROXY CARD IN THE ENCLOSED RETURN ENVELOPE. PROMPTLY VOTING YOUR SHARES WILL ENSURE THE PRESENCE OF A QUORUM AT THE ANNUAL MEETING AND WILL SAVE US THE EXPENSE OF FURTHER SOLICITATION.

By Order of the Board of Directors | ​ | ​ |
| ​ | ​ |
| ​ | ​ |
Jonathan Paris, SVP, Secretary and General Counsel | ​ | ​ |

Lowell, Massachusetts
April 8, 2022
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