Tectonic Therapeutic (TECX) withholds CEO shares for RSU taxes

Rhea-AI Filing Summary

Tectonic Therapeutic, Inc. reported a routine share withholding related to its Chief Executive Officer, Alise Reicin. On February 4, 2026, the company withheld 4,104 shares of common stock at $23.22 per share to cover her tax obligations from vesting restricted stock units granted on February 4, 2025.

Following this transaction, Reicin beneficially owned 235,047 shares directly. An additional 124,530 shares were held indirectly through the Reicin-Boiarsky Family Trust, where she may share voting and dispositive power but disclaims full beneficial ownership beyond her economic interest.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider REICIN ALISE

Role Chief Executive Officer

Type	Security	Shares	Price	Value
Tax Withholding	Common Stock	4,104	$23.22	$95K
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 235,047 shares (Direct); Common Stock — 124,530 shares (Indirect, By Trust)

Footnotes (1)

1. This transaction reported represents the withholding of shares by the Issuer to satisfy the Reporting Person's tax withholding obligations in connection with the vesting and settlement of the restricted stock units granted on February 4, 2025. These shares are held by the Reicin-Boiarsky Family Trust (the "Trust"). The Reporting Person's spouse is a co-trustee of the Trust. Accordingly, the Reporting Person may be deemed to have shared voting and dispositive power over the securities held by the Trust. The Reporting Person disclaims beneficial ownership of the shares held by the Trust except to the extent of her pecuniary interest therein, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of these securities for purposes of Section 16 or for any other purpose.

Form 4 Insider Transactions: What Each Field Means →

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^*

REICIN ALISE

(Last) (First) (Middle)

C/O TECTONIC THERAPEUTIC, INC.

490 ARSENAL WAY, SUITE 200

(Street)

WATERTOWN MA 02472

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Tectonic Therapeutic, Inc. [ TECX ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
02/04/2026

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	02/04/2026		F		4,104(1)	D	$23.22	235,047	D
Common Stock								124,530	I	By Trust(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)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. This transaction reported represents the withholding of shares by the Issuer to satisfy the Reporting Person's tax withholding obligations in connection with the vesting and settlement of the restricted stock units granted on February 4, 2025.

2. These shares are held by the Reicin-Boiarsky Family Trust (the "Trust"). The Reporting Person's spouse is a co-trustee of the Trust. Accordingly, the Reporting Person may be deemed to have shared voting and dispositive power over the securities held by the Trust. The Reporting Person disclaims beneficial ownership of the shares held by the Trust except to the extent of her pecuniary interest therein, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of these securities for purposes of Section 16 or for any other purpose.

	/s/ Daniel Lochner, Attorney-in-Fact	02/10/2026
	** 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.

FAQ

What insider transaction did Tectonic Therapeutic (TECX) disclose for its CEO?

Tectonic Therapeutic disclosed that its CEO, Alise Reicin, had 4,104 common shares withheld on February 4, 2026. The issuer withheld these shares at $23.22 each to satisfy tax obligations tied to previously granted restricted stock units that had vested and settled.

Was the Tectonic Therapeutic (TECX) CEO’s Form 4 transaction an open-market sale?

The Form 4 reports a tax withholding transaction, not an open-market sale. The issuer withheld 4,104 shares of common stock at $23.22 per share to cover CEO Alise Reicin’s tax obligations linked to vesting restricted stock units granted on February 4, 2025.

How many Tectonic Therapeutic (TECX) shares does the CEO hold after this filing?

After the reported withholding, CEO Alise Reicin beneficially owned 235,047 Tectonic Therapeutic common shares directly. Additionally, 124,530 shares were held indirectly by the Reicin-Boiarsky Family Trust, where she may share voting and dispositive power but disclaims full beneficial ownership.

What is the role of the Reicin-Boiarsky Family Trust in the Tectonic (TECX) holdings?

The Reicin-Boiarsky Family Trust holds 124,530 Tectonic Therapeutic common shares. The CEO’s spouse is a co-trustee, and Alise Reicin may share voting and dispositive power. She disclaims beneficial ownership beyond her pecuniary interest, meaning the trust, not she individually, formally holds those shares.

Why were Tectonic Therapeutic (TECX) shares withheld from the CEO on February 4, 2026?

Shares were withheld to cover CEO Alise Reicin’s tax obligations from vesting restricted stock units. Restricted stock units granted on February 4, 2025, vested and settled, and the issuer retained 4,104 common shares at $23.22 each instead of the CEO selling shares to pay taxes.