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

Rhea-AI Filing Summary

Sangamo Therapeutics insider filing shows routine RSU vesting and tax-withholding disposition. On 08/24/2025 the reporting person, Scott B. Willoughby (SVP, Chief Legal Officer, Secretary and Director), had 1,434 shares disposed of at a price of $0.5863 per share to satisfy mandatory tax withholding related to RSUs that vested that day.

After the withholding disposition the reporting person beneficially owns 748,243 shares. The filing details scheduled vesting: 2,574 shares from a Feb 24, 2023 RSU grant (with remaining installments through Feb 24, 2026), 178,125 shares from a Jan 22, 2024 RSU grant vesting through Jan 22, 2026, and 120,000 shares from a Feb 25, 2025 RSU grant with one-quarter vesting on Feb 25, 2026 and the remainder in eight quarterly installments. All vesting is conditioned on Continuous Service and any applicable acceleration under the 2018 EIP.

Positive

• Substantial post-transaction ownership of 748,243 shares remains, indicating continued insider alignment with shareholders
• Transactions were plan-driven and non-discretionary (mandatory tax withholding on vested RSUs), reducing concerns about opportunistic insider selling

Negative

• None.

Insights

Financial Analyst

TL;DR: Routine RSU vesting and tax-withholding; no material change to insider stake.

The Form 4 reports a mandatory withholding disposition of 1,434 shares at $0.5863 per share tied to vested RSUs on 08/24/2025. This was a non-discretionary, plan-driven transaction and not an open-market sale. Post-transaction beneficial ownership is reported as 748,243 shares. The filing also outlines multiple RSU grants with scheduled quarterly vesting through 2026, indicating continued compensation alignment with the issuer. From a financial-impact perspective this disclosure is administrative and not materially dilutive beyond standard equity compensation mechanics.

Corporate Governance Expert

TL;DR: Insider retained significant ownership; transaction reflects standard plan mechanics and tax compliance.

The filing documents a tax-withholding disposition under the Issuer's Amended and Restated 2018 Equity Incentive Plan. The transaction is explicitly described as required for withholding and is reported as a disposition for Form 4 purposes only. The detailed vesting schedules and service-condition language show standard governance controls around equity compensation and potential acceleration provisions. No leadership change, discretionary trading, or unusual compensation action 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
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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^*

Willoughby Scott B.

(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 LEGAL OFFICER, SECY

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		1,434(1)	D	$0.5863	748,243(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) 2,574 shares resulting from the August 24, 2025 vesting installment of the Reporting Person's February 24, 2023 RSU grant, and the remaining 8,016 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/ Prathyusha Duraibabu, 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 the SGMO Form 4 filed for Scott B. Willoughby report?

The filing reports a mandatory tax-withholding disposition of 1,434 shares from vested RSUs on 08/24/2025 at a price of $0.5863 per share.

How many shares does the reporting person beneficially own after the transaction?

The reporting person beneficially owns 748,243 shares following the reported withholding disposition.

Why were the 1,434 shares disposed of according to the Form 4?

The shares were surrendered solely for mandatory tax withholding related to vested restricted stock units under the Issuer's 2018 Equity Incentive Plan.

What RSU vesting schedules are disclosed in the filing?

The filing discloses: (a) 2,574 shares from the Feb 24, 2023 RSU grant with remaining vesting through Feb 24, 2026, (b) 178,125 shares from the Jan 22, 2024 RSU grant vesting through Jan 22, 2026, and (c) 120,000 shares from the Feb 25, 2025 RSU grant with 1/4 vesting on Feb 25, 2026 and the rest in eight quarterly installments.

Was this a market sale or discretionary trade by the insider?

No. The filing states the disposition was for mandatory tax withholding and "does not represent a discretionary trade" by the reporting person.