Jake Simson - Jun 17, 2025 Form 4 Insider Report for Septerna, Inc. (SEPN)

Role: Director
Signature: /s/ Jeffrey Finer, Attorney-in-Fact
Stock symbol: SEPN
Transactions as of: Jun 17, 2025
Transactions value $: $0
Form type: 4
Date filed: 6/20/2025, 06:40 PM
Previous filing: Jun 13, 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Simson Jake	Director	C/O SEPTERNA, INC., 250 EAST GRAND AVENUE, SOUTH SAN FRANCISCO	/s/ Jeffrey Finer, Attorney-in-Fact	2025-06-20	0001863094

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	SEPN	Stock Option (Right to Buy)	Award	$0	+16.6K		$0.00	16.6K	Jun 17, 2025	Common Stock	16.6K	$10.24	Direct	F1, F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	The shares underlying the stock option will vest in full upon the earlier of (i) June 17, 2026 or (ii) the Issuer's next annual meeting of stockholders, subject to the Reporting Person's continued service to the Issuer through such vesting date.
F2	Under the Reporting Person's arrangement with RA Capital Management, L.P. (the "Adviser"), the Reporting Person holds the option for the benefit of the R.A. Capital Healthcare Fund, L.P. (the "Fund") and R.A. Capital Nexus Fund III, L.P. (the "Nexus Fund III"). The Reporting Person is obligated to turn over to the Adviser any net cash or stock received upon exercise of the option, which will offset advisory fees owed by the Fund and the Nexus Fund III to the Adviser. The Reporting Person therefore disclaims beneficial ownership of the option and underlying common stock.

Content

The shares underlying the stock option will vest in full upon the earlier of (i) June 17, 2026 or (ii) the Issuer's next annual meeting of stockholders, subject to the Reporting Person's continued service to the Issuer through such vesting date.

Under the Reporting Person's arrangement with RA Capital Management, L.P. (the "Adviser"), the Reporting Person holds the option for the benefit of the R.A. Capital Healthcare Fund, L.P. (the "Fund") and R.A. Capital Nexus Fund III, L.P. (the "Nexus Fund III"). The Reporting Person is obligated to turn over to the Adviser any net cash or stock received upon exercise of the option, which will offset advisory fees owed by the Fund and the Nexus Fund III to the Adviser. The Reporting Person therefore disclaims beneficial ownership of the option and underlying common stock.