Tectonic Therapeutic (TECX) CSO exercises options and sells 172 shares under 10b5-1 plan

Rhea-AI Filing Summary

Tectonic Therapeutic Chief Scientific Officer Peter McNamara exercised options for 172 shares of common stock at $14.71 per share and the same day sold 172 shares in an open-market trade at $35.00 per share under a pre-arranged Rule 10b5-1 plan. Following these transactions, he directly holds 55,285 common shares and 7,873 employee stock options, indicating a small, routine liquidity event relative to his overall position.

Insider Trade Summary 10b5-1

Net Seller: 172 shares ($6,020)

Net Sell 3 txns

Insider McNamara Peter

Role Chief Scientific Officer

Sold 172 shs ($6K)

Type	Security	Shares	Price	Value
Exercise	Employee Stock Option (Right to Buy)	172	$0.00	--
Exercise	Common Stock	172	$14.71	$3K
Sale	Common Stock	172	$35.00	$6K

Holdings After Transaction: Employee Stock Option (Right to Buy) — 7,873 shares (Direct, null); Common Stock — 55,457 shares (Direct, null)

Footnotes (1)

1. This exercise and subsequent sale was made pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 14, 2025. The shares subject to the option vest in 48 equal monthly installments beginning on October 25, 2025, subject to the Reporting Person's continued service to the Issuer on each such vesting date.

Key Figures

Shares sold: 172 shares Sale price: $35.00/share Options exercised: 172 options +4 more

7 metrics

Shares sold 172 shares Open-market sale of common stock on June 30, 2026

Sale price $35.00/share Price for 172 common shares sold

Options exercised 172 options Employee stock options converted into common shares

Option exercise price $14.71/share Exercise price for employee stock options

Common shares held after 55,285 shares Direct ownership after transactions

Options held after 7,873 options Employee stock options remaining after exercise

Option expiration September 24, 2035 Expiration date of employee stock option grant

Key Terms

Rule 10b5-1 trading plan, Employee Stock Option (Right to Buy), open-market sale, Chief Scientific Officer, +1 more

5 terms

Rule 10b5-1 trading plan regulatory

"This exercise and subsequent sale was made pursuant to a Rule 10b5-1 trading plan adopted"

A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.

Employee Stock Option (Right to Buy) financial

"security_title": "Employee Stock Option (Right to Buy)""

open-market sale financial

"transaction_action": "open-market sale""

An open-market sale is when a shareholder sells existing shares directly on a public exchange to any willing buyer, rather than through a private deal. Think of it like putting goods on a busy market stall where price is set by supply and demand; for investors it matters because such sales increase available supply, can put short-term downward pressure on the stock price, and signal changes in liquidity or investor confidence.

Chief Scientific Officer financial

"officer_title": "Chief Scientific Officer""

derivative exercise/conversion financial

"transaction_action": "derivative exercise/conversion""

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Form 4 Insider Transactions: What Each Field Means →

Available on EDGAR 07/01/2026 - 05:20 PM Accepted by SEC EDGAR 07/01/2026 - 05:19 PM Learn about SEC filing dates

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).

X

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^*

McNamara Peter

(Last) (First) (Middle)

C/O TECTONIC THERAPEUTIC, INC.

490 ARSENAL WAY, SUITE 200

(Street)

WATERTOWN MASSACHUSETTS 02472

(City) (State) (Zip)

UNITED STATES

(Country)

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

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
06/30/2026

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)
			Code	V	Amount	(A) or (D)	Price
Common Stock	06/30/2026		M(1)		172	A	$14.71	55,457	D
Common Stock	06/30/2026		S(1)		172	D	$35	55,285	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
Employee Stock Option (Right to Buy)	$14.71	06/30/2026		M(1)			172	(2)	09/24/2035	Common Stock	172	$0	7,873	D

Explanation of Responses:

1. This exercise and subsequent sale was made pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 14, 2025.

2. The shares subject to the option vest in 48 equal monthly installments beginning on October 25, 2025, subject to the Reporting Person's continued service to the Issuer on each such vesting date.

	/s/ Daniel Lochner, Attorney-in-Fact	07/01/2026
	** 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)

FAQ

What insider transactions did TECX Chief Scientific Officer Peter McNamara report?

Peter McNamara reported exercising options for 172 TECX common shares and selling 172 shares in an open-market transaction. These same-day moves combined a derivative exercise at a lower price with a market sale at a higher price, reflecting a routine exercise-and-sell pattern.

At what prices did Peter McNamara exercise and sell Tectonic Therapeutic (TECX) shares?

He exercised employee stock options at an exercise price of $14.71 per share and sold 172 common shares at $35.00 per share. This spread reflects the option’s built-in value realized through the open-market sale on the same transaction date.

How many Tectonic Therapeutic (TECX) shares does Peter McNamara hold after this Form 4?

After the reported transactions, Peter McNamara directly holds 55,285 shares of Tectonic Therapeutic common stock. He also retains 7,873 employee stock options, indicating that the 172-share sale represents a very small portion of his overall equity exposure.

Was the TECX insider transaction by Peter McNamara under a Rule 10b5-1 plan?

Yes. A footnote states the option exercise and subsequent sale were made under a Rule 10b5-1 trading plan adopted on November 14, 2025. Such pre-arranged plans typically indicate the timing was scheduled in advance rather than a discretionary market-timing decision.

What happens to Peter McNamara’s TECX stock options after this exercise and sale?

The filing shows 7,873 employee stock options remaining after exercising 172 options tied to common shares. These options vest in 48 equal monthly installments starting October 25, 2025, contingent on his continued service, and expire on September 24, 2035.