Senti Biosciences CEO has 157,312 shares withheld

Q: How many SNTI shares did Timothy K. Lu have withheld?

The issuer withheld 157,312 common shares on October 21, 2026, to satisfy income tax withholding and remittance obligations in connection with net settlement of certain time-based restricted stock unit awards. The shares were not an open-market sale.

Q: How many SNTI shares did Timothy K. Lu hold directly afterward?

Lu directly held 482,271 common shares after the October 21, 2026 transaction.

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Rhea-AI Filing Summary

Senti Biosciences Holdings, Inc. (SNTI) CEO and director Timothy K. Lu reported that 157,312 common shares were withheld by the issuer on October 21, 2026, to satisfy income tax withholding and remittance obligations in connection with net settlement of certain time-based restricted stock unit awards. The shares were not an open-market sale. Lu directly held 482,271 shares afterward. Separate indirect holdings are listed as 52,839 shares held by his spouse and 52,839 shares held by Luminen Services, LLC, trustee of the Luminen Trust; Lu is the trust’s settlor and disclaims Section 16 beneficial ownership except to the extent of his pecuniary interest, if any. No Rule 10b5-1 plan is reported.

Insider Trade Summary

Tax Withholding: 157,312 shares

Tax Withholding 3 txns

Insider Lu Timothy K

Role CEO

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock ^F1	157,312	$0.00	$0.00
holding	Common Stock	--	--	--
holding	Common Stock ^F2	--	--	--

Holdings After Transaction: Common Stock — 482,271 shares (Direct); Common Stock — 52,839 shares (Indirect, By spouse); Common Stock — 52,839 shares (Indirect, See footnote)

Footnotes (2)

F1. Represents the number of shares of common stock that have been withheld by the Issuer to satisfy its income tax withholding and remittance obligations in connection with the net settlement of certain time-based restricted stock unit awards and does not represent an open market sale.
F2. The shares are held by Luminen Services, LLC, as trustee of the Luminen Trust, of which the reporting person is the settlor. The reporting person disclaims Section 16 beneficial ownership of the securities, except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed to be an admission that he has beneficial ownership of such shares for Section 16 or any other purpose.

Key Figures

Shares withheld for tax obligations: 157,312 shares Direct common shares held after transaction: 482,271 shares Indirect common shares held by spouse: 52,839 shares +1 more

4 metrics

Shares withheld for tax obligations 157,312 shares October 21, 2026; connected to net settlement of certain time-based restricted stock unit awards

Direct common shares held after transaction 482,271 shares Timothy K. Lu, October 21, 2026

Indirect common shares held by spouse 52,839 shares Reported as held by spouse

Indirect common shares held by Luminen Trust 52,839 shares Held by Luminen Services, LLC as trustee of the Luminen Trust

Key Terms

net settlement, time-based restricted stock unit awards, income tax withholding and remittance obligations, Section 16 beneficial ownership

4 terms

net settlement financial

"in connection with the net settlement"

time-based restricted stock unit awards financial

"certain time-based restricted stock unit awards"

income tax withholding and remittance obligations financial

"satisfy its income tax withholding and remittance obligations"

Section 16 beneficial ownership regulatory

"disclaims Section 16 beneficial ownership"

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

How many SNTI shares did Timothy K. Lu have withheld?

The issuer withheld 157,312 common shares on October 21, 2026, to satisfy income tax withholding and remittance obligations in connection with net settlement of certain time-based restricted stock unit awards. The shares were not an open-market sale.

How many SNTI shares did Timothy K. Lu hold directly afterward?

Lu directly held 482,271 common shares after the October 21, 2026 transaction.

AI-generated analysis. How Rhea-AI works. Not financial advice.

Form 4 Insider Transactions: What Each Field Means →

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Available on EDGAR 10/23/2026 - 04:38 PM EDT Accepted by SEC EDGAR 10/23/2026 - 04:37 PM EDT

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^*

Lu Timothy K

(Last)

(First)

(Middle)

C/O SENTI BIOSCIENCES, INC.

2 CORPORATE DRIVE FIRST FLOOR

(Street)

SOUTH SAN FRANCISCO

CALIFORNIA

94080

(City)

(State)

(Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Senti Biosciences Holdings, Inc. [ SNTI ]

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

X	Director	10% Owner
X	Officer (give title below)	Other (specify below)
	CEO

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
10/21/2026

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

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

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

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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	10/21/2026		F		157,312⁽¹⁾	D	$0	482,271	D
Common Stock								52,839	I	By spouse
Common Stock								52,839	I	See footnote⁽²⁾

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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)

Explanation of Responses:

1. Represents the number of shares of common stock that have been withheld by the Issuer to satisfy its income tax withholding and remittance obligations in connection with the net settlement of certain time-based restricted stock unit awards and does not represent an open market sale.

2. The shares are held by Luminen Services, LLC, as trustee of the Luminen Trust, of which the reporting person is the settlor. The reporting person disclaims Section 16 beneficial ownership of the securities, except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed to be an admission that he has beneficial ownership of such shares for Section 16 or any other purpose.

Remarks:

	/s/ Robert Cutler, attorney-in-fact	10/23/2026
	** 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.
* Form 4: SEC 1474 (03-26)

Source: View Original Filing on SEC EDGAR