The Company’s Certificate of Incorporation authorizes the Company to issue up to 5,000,000 shares of preferred stock, which may be issued at the discretion of the Company’s Board of Directors. As of December 31, 2020, no shares of the Company’s preferred stock have been issued or are outstanding.

In June 2020, the Company’s stockholders approved an amendment to the Company’s Certificate of Incorporation to increase the total number of shares of the Company’s common stock authorized for issuance from 160,000,000 shares to 320,000,000 shares. As of December 31, 2020, 142,063,203 shares of the Company’s common stock are outstanding.

In connection with the collaboration agreement with BIMA described in Note 4 of these Consolidated Financial Statements, the Company entered into a stock purchase agreement with BIMA, pursuant to which BIMA agreed to purchase the Biogen Shares at a price per share of $9.2137, for an aggregate purchase price of $225.0 million. The Company closed the sale of the Biogen Shares in April 2020.

In April 2019, the Company completed an underwritten public offering of its common stock, in which the Company sold an aggregate of 12.7 million shares of its common stock at a public offering price of $11.50 per share. The net proceeds to the Company from the sale of shares in this offering, after deducting underwriting discounts and commissions and other offering expenses, were approximately $136.3 million.

In April 2018, the Company completed an underwritten public offering of its common stock, in which the Company sold an aggregate of 14.2 million shares of its common stock at a public offering price of $16.25 per share. The net proceeds to the Company from the sale of shares in this offering, after deducting underwriting discounts and commissions and other offering expenses, were approximately $215.8 million.

In August 2020, the Company entered into an Open Market Sale Agreement℠ with Jefferies LLC (“Jefferies”) with respect to an at-the-market offering program under which the Company may offer and sell, from time to time at its sole discretion, shares of the Company’s common stock having an aggregate offering price of up to $150.0 million through Jefferies as the Company’s sales agent or principal. The Company is not obligated to sell any shares under the sales agreement. As of December 31, 2020, no shares had been sold under the sales agreement.

In June 2018, the Company’s stockholders approved the Sangamo Therapeutics, Inc. 2018 Equity Incentive Plan (the “2018 Plan”). In connection with the approval of the 2018 Plan, no additional equity awards will be granted under the previous 2013 Plan, however all outstanding equity awards under the 2013 Plan will continue to be subject to the terms and conditions as set forth in the agreements evidencing such awards and the terms of the 2013 Plan.

In May 2020, the Company’s stockholders approved an amendment and restatement of the 2018 Plan, to, among other things, increase the aggregate number of shares of the Company’s common stock reserved for issuance under the 2018 Plan by 9,900,000 shares.

The exercise price of a stock option granted under the 2018 Plan may not be less than 100% of the fair market value of the Company's common stock subject to the stock option on the date of grant, and the option term will not exceed 10 years. If the person to whom the stock option is granted is a 10% stockholder of the Company, and the stock option granted qualifies as an incentive stock option, then the exercise price per share will not be less than 110% of the fair market value of the Company’s common stock on the date of grant, and the option term will not exceed five years. Generally, stock options granted under the 2018 Plan vest over four years at a rate of 25% on the one-year anniversary of the date of grant and 1/48 per month thereafter and expire 10 years after the date of grant, or earlier upon termination of employment or services to the Company.

The number of shares of common stock reserved for issuance under the 2018 Plan will be reduced: (i) on a 1-for-1 basis for each share of common stock subject to a stock option or stock appreciation right granted under the plan, (ii) by a fixed

Shares subject to any outstanding stock options or other awards under the 2018 Plan that expire or otherwise terminate prior to the issuance of the shares subject to those stock options or awards will be available for subsequent issuance under the 2018 Plan. Any unvested shares issued under the 2018 Plan that the Company subsequently purchases, pursuant to repurchase rights under the 2018 Plan, will be added back to the number of shares reserved for issuance under the 2018 Plan on a 1-for-1 basis or a 1.33-for-1 basis (depending on the ratio at which the share reserve was debited for the original award) and will accordingly be available for subsequent issuance in accordance with the terms of the 2018 Plan.

On June 2018, the Company’s stockholders approved an amendment and restatement of the Company’s 2010 Employee Stock Purchase Plan (“the ESPP”). As amended, the ESPP provides for a total of 4.6 million shares of common stock reserved for issuance thereunder. Eligible employees may purchase common stock at 85% of the lesser of the fair market value of the Company’s common stock on the first day of the applicable two-year offering period or the last day of the applicable six-month purchase period. As of December 31, 2020, there were 2,483,218 shares of the Company’s common stock reserved for future issuance under the ESPP. The ESPP expired on April 30, 2020. The ongoing offering will continue through the end of its 24 months offering period ending on October 29, 2021 at which point the ESPP will be fully terminated.


	Number of Shares	Weighted- Average Exercise per Share Price		Weighted-Average Remaining Contractual Term	Aggregate Intrinsic Value
				(In years)	(In thousands)
Options outstanding at December 31, 2019	9,829,287	$	10.71
Options granted	4,563,425	$	8.09
Options exercised	(1,162,268)	$	8.02
Options canceled	(1,751,746)	$	10.19
Options outstanding at December 31, 2020	11,478,698	$	10.02	7.80	$	69,616
Options vested and expected to vest at December 31, 2020	11,478,698	$	10.02	7.80	$	69,616
Options exercisable at December 31, 2020	5,127,517	$	10.71	6.48	$	29,025

At December 31, 2020, the aggregate intrinsic values of outstanding and exercisable options were $69.6 million and $29.0 million, respectively. The aggregate intrinsic value of options vested and expected to vest as of December 31, 2020, 2019 and 2018 was $69.6 million, $7.5 million and $24.5 million, respectively.

During 2020, 2019 and 2018, the Company awarded 2,517,101, 834,745, and 346,055 RSUs, respectively. The RSUs awarded in 2020, 2019 and 2018 had an average grant date fair value per award of $8.06, $9.49 and $17.87, respectively. These awards generally vest in a series of three successive equal annual installments. The aggregate fair value of RSUs vested during 2020, 2019 and 2018 was $3.7 million, $2.0 million and $0.6 million, respectively.


	Number of Shares	Weighted-Average Remaining Contractual Term	Aggregate Intrinsic Value
		(In years)	(In thousands)
RSUs outstanding at December 31, 2019	862,850
RSUs awarded	2,517,101
RSUs released	(324,305)
RSUs forfeited	(384,118)
RSUs outstanding at December 31, 2020	2,671,528	1.19	$	41,689
RSUs vested and expected to vest at December 31, 2020	2,671,528	1.19	$	41,689

RSUs that vested in 2020, 2019 and 2018 were net-share settled such that the Company withheld shares with value equivalent to the employees’ minimum statutory obligation for the applicable income and other employment taxes and remitted the cash to the appropriate taxing authorities. The total shares withheld were approximately 90,617, 39,160, and 20,193 for 2020, 2019 and 2018, respectively, and were based on the value of the RSUs on their respective issuance dates as determined by the Company’s closing stock price. Total payments for the employees’ tax obligations to taxing authorities were $0.8 million, $0.4 million and $0.3 million in 2020, 2019 and 2018, respectively and are reflected as a financing activity within the accompanying Consolidated Statements of Cash Flows. These net-share settlements had the effect of share repurchases by the Company as they reduced and retired the number of shares that would have otherwise been issued as a result of the vesting and did not represent an expense to the Company.