[Form 4] Sangamo Therapeutics, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Sangamo Therapeutics insider Nathalie Dubois-Stringfellow reported a small disposition tied to RSU tax withholding and continues to hold a substantial equity stake. The Form 4 shows that on 08/24/2025 she surrendered 1,792 shares to the company for mandatory tax withholding at a price of $0.5863 per share related to vested restricted stock units under the 2018 Equity Incentive Plan.

After the withholding disposition, the reporting person beneficially owns 766,089 shares. The filing details the schedule of outstanding RSU grants and future vesting: remaining installments from a 2023 grant, a 2024 grant vesting through January 22, 2026, and a 2025 grant with a first vesting on February 25, 2026, all subject to continuous service and plan acceleration provisions.

Positive

• Reporting person retains substantial ownership of 766,089 shares, indicating continued alignment with shareholders
• Disposition was tax withholding only, not an open-market sale, reflecting administrative processing of vested RSUs

Negative

• Small reduction of reported shares due to surrender of 1,792 shares for mandatory tax withholding

Insights

Securities Analyst

TL;DR: A routine RSU vesting tax-withholding disposition; reporting person still holds a sizable stake, no open-market sale observed.

The transaction code indicates a mandatory tax withholding related to RSU vesting rather than an open-market sale, which reduces reported shares by 1,792 at $0.5863 per share. The remaining beneficial ownership of 766,089 shares reflects vested and unvested RSUs from multiple grants with scheduled future vesting through 2026. This is a routine administrative disposition that does not change the executives underlying long-term equity exposure to SGMO.

Corporate Governance Expert

TL;DR: Filing documents expected tax-withholding mechanics on vested RSUs and confirms ongoing service-based vesting schedules.

The Form 4 clearly describes that withheld shares were surrendered solely for tax obligations under the companys Amended and Restated 2018 Equity Incentive Plan. The disclosure of vesting schedules and acceleration provisions provides transparency on future potential dilution and insider alignment with shareholder interests. No sale or transfer to third parties is reported.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Dubois-Stringfellow Nathalie

(Last) (First) (Middle)

C/O SANGAMO THERAPEUTICS, INC.

501 CANAL BLVD.

(Street)

RICHMOND CA 94084

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
SANGAMO THERAPEUTICS, INC [ SGMO ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	SVP-CHIEF DEVELOPMENT OFFICER

3. Date of Earliest Transaction (Month/Day/Year)
08/24/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	08/24/2025		F		1,792(1)	D	$0.5863	766,089(2)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Represents shares underlying the portion of a restricted stock unit ("RSU") grant that vested on August 24, 2025, which were surrendered by the Reporting Person solely for mandatory tax withholding purposes using the Issuer's closing stock price on August 22, 2025 of $0.5863/share, pursuant to the terms of the Issuer's Amended and Restated 2018 Equity Incentive Plan, as amended (the "2018 EIP"). This required tax withholding transaction is deemed to constitute a disposition of these shares to the Issuer for reporting purposes and does not represent a discretionary trade by the Reporting Person in the open market or otherwise.

2. Includes: (a) 3,218 shares resulting from the August 24, 2025 vesting installment of the Reporting Person's February 24, 2023 RSU grant, and the remaining 10,020 shares will vest in successive equal quarterly installments through February 24, 2026, (b) 178,125 shares subject to the Reporting Person's January 22, 2024 RSU grant that will vest in successive equal quarterly installments through January 22, 2026 and (c) 120,000 shares subject to Reporting Person's February 25, 2025 RSU grant that will vest as to one-quarter (1/4) of the shares on February 25, 2026, and the remainder of the shares will vest in 8 successive equal quarterly installments thereafter. The vesting of all such RSU grants is subject to the Reporting Person's Continuous Service (as defined in the 2018 EIP) through each such date and subject to acceleration as provided in the 2018 EIP.

	/s/ Scott Willoughby, Attorney-in-Fact	08/26/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did Nathalie Dubois-Stringfellow report on Form 4 for SGMO?

She reported surrendering 1,792 shares on 08/24/2025 for mandatory tax withholding related to vested RSUs and now beneficially owns 766,089 shares.

Was the transaction an open-market sale or a tax withholding?

The transaction was a tax withholding disposition related to RSU vesting, not a discretionary sale in the open market.

At what price were the withheld shares processed?

The shares were withheld using the issuer's closing price of $0.5863 per share on August 22, 2025, per the filing.

What RSU grants and vesting schedules are disclosed in the filing?

Disclosure includes a 2023 RSU grant with remaining quarterly vesting through Feb 24, 2026, a 2024 grant vesting through Jan 22, 2026, and a 2025 grant with first vesting Feb 25, 2026 and subsequent quarterly vesting.

Does the filing indicate any acceleration or conditions on vesting?

Yes, all RSU vesting is subject to continuous service requirements and potential acceleration provisions as provided in the 2018 EIP.