[Form 4] Sera Prognostics, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Sera Prognostics insider disclosure: John J. Boniface, the company's Chief Scientific Officer, reported a non-discretionary sale of restricted stock to satisfy tax-withholding obligations. On 08/08/2025 the reporting person sold 7,094 shares that were withheld upon the vesting of RSUs; the issuer required a "sell-to-cover" to satisfy taxes.

The filing reports a weighted-average sale price of $2.54 (block trades ranged from $2.28 to $2.73) and shows the reporting person beneficially owns 160,888 shares following the transaction. No derivative transactions were reported.

Positive

• Reporting person retains significant ownership: 160,888 shares remain beneficially owned after the sell-to-cover transaction.
• Sale was non-discretionary: The issuer mandated the sell-to-cover to satisfy tax withholding on vested RSUs, indicating administrative purpose rather than a voluntary liquidation.

Negative

• None.

Insights

Corporate Governance Expert

TL;DR: A routine, mandatory sell-to-cover for RSU tax withholding; not a discretionary insider exit and materially neutral.

The reported sale was performed to satisfy tax withholding on vested RSUs and is explicitly described as mandated by the issuer. Such transactions are standard compensation-related events and do not reflect an independent decision to liquidate holdings. The insider retains 160,888 shares after the sale, and there are no reported derivative positions. From a governance perspective this is a routine administrative disclosure with limited informational value for corporate control or strategy.

Securities Analyst

TL;DR: The sale of 7,094 shares at a weighted $2.54 was a block sell-to-cover and appears immaterial to company valuation.

The transaction was executed as part of a block trade at prices between $2.28 and $2.73, producing a weighted average of $2.54. Because the sale was to cover tax obligations from RSU vesting and not a discretionary sale, it does not signal a change in insider confidence. The remaining direct beneficial ownership of 160,888 shares sustains the insider's exposure to the company’s equity, suggesting minimal near-term market impact.

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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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^*

Boniface John J.

(Last) (First) (Middle)

C/O SERA PROGNOSTICS, INC.

2749 EAST PARLEYS WAY, SUITE 200

(Street)

SALT LAKE CITY UT 84109

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
SERA PROGNOSTICS, INC. [ SERA ]

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

3. Date of Earliest Transaction (Month/Day/Year)
08/08/2025

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
Class A Common Stock	08/08/2025		S		7,094(1)	D	$2.54(2)	160,888	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 the number of shares sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of restricted stock units ("RSUs"). The sale is mandated by the Issuer's election to require the satisfaction of tax withholding obligations to be funded by "sell to cover" transactions and does not represent a discretionary transaction by the Reporting Person.

2. The price reported is a weighted average price. These shares were sold as part of a block trade in multiple transactions at prices ranging from $2.28 to $2.73, inclusive. The Reporting Person will provide to the staff of the Securities and Exchange Commission, the issuer, or any security holder of the issuer, upon request, full information regarding the number of shares sold at each separate price with regard to the block trade.

	/s/ Benjamin G. Jackson, Attorney-in-fact	08/11/2025
	** 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 Form 4 for SERA report?

The Form 4 reports that CSO John J. Boniface sold 7,094 shares on 08/08/2025 to cover tax withholding tied to RSU vesting.

At what price were the SERA shares sold?

The filing reports a weighted-average sale price of $2.54; the block trade prices ranged from $2.28 to $2.73.

Was the sale discretionary or mandatory?

The sale was mandated by the issuer as a sell-to-cover to satisfy tax withholding and is described as not a discretionary transaction by the reporting person.

How many SERA shares does the insider own after the transaction?

Following the transaction the reporting person beneficially owns 160,888 shares, held directly.

Were any derivative securities reported in this Form 4?

No derivative securities were reported; Table II of the filing contains no entries.