[SCHEDULE 13G] Sera Prognostics, Inc. SEC Filing

Rhea-AI Filing Summary

Sera Prognostics, Inc. reporting persons Whetstone Capital Advisors, LLC and David Atterbury disclosed beneficial ownership of 3,632,371 shares of Class A common stock, equal to 9.9% of the class as of the required reporting date. The filing shows no sole voting or dispositive power; all voting and dispositive power is shared.

The Schedule 13G states the shares are not held to change or influence control of the issuer. The reporting address and CUSIP are provided, and the statement is signed by Mr. Atterbury as Manager and CCO/President.

Positive

• Material stake disclosed: 3,632,371 shares representing 9.9% of Class A common stock
• Shared voting/dispositive power disclosed: transparency on how voting authority is held
• Certification of passive intent: filer states shares are not held to influence control

Negative

• None.

Insights

Financial Analyst

9.9% stake is material but below typical 10% activism trigger; ownership is disclosed as shared, not sole.

The filing reports a near-double-digit position of 3,632,371 shares representing 9.9% of SERA's Class A stock. Shared voting and dispositive power suggests the position may be held on behalf of clients or through pooled vehicles rather than direct control. The certification that the position is not intended to influence control reduces immediate governance risk, though the size of the stake warrants monitoring for future schedule changes.

Corporate Governance Expert

Disclosure is material for governance monitoring; no current indication of control intent.

Reporting persons filed under Schedule 13G, indicating a passive reporting posture consistent with institutional or insider reporting categories. Because the position equals 9.9%, just below many regulatory or market attention thresholds, investors and the board should note the holder's rights are shared and the filer affirms no plan to change control. Future filings could alter this picture if voting patterns or intentions change.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

Sera Prognostics, Inc.

(Name of Issuer)

Class A Common Stock, par value $0.0001 per share

(Title of Class of Securities)

81749D107

(CUSIP Number)

06/30/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 81749D107

1

Names of Reporting Persons

Whetstone Capital Advisors, LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

KANSAS

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 3,632,371.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 3,632,371.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

3,632,371.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

9.9 %

12

Type of Reporting Person (See Instructions)

IA, OO

SCHEDULE 13G

CUSIP No. 81749D107

1

Names of Reporting Persons

David Atterbury

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 3,632,371.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 3,632,371.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

3,632,371.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

9.9 %

12

Type of Reporting Person (See Instructions)

HC, IN

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Sera Prognostics, Inc.
(b)	Address of issuer's principal executive offices: 2749 East Parleys Way, Suite 200, Salt Lake City, Utah 84109
Item 2.
(a)	Name of person filing: Whetstone Capital Advisors, LLC ("WCA") and Mr. David Atterbury (collectively the "Reporting Persons").
(b)	Address or principal business office or, if none, residence: 2001 Shawnee Mission Parkway, Shawnee Mission, Kansas 66205
(c)	Citizenship: United States of America
(d)	Title of class of securities: Class A Common Stock, par value $0.0001 per share
(e)	CUSIP No.: 81749D107
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: 3, 632, 371
(b)	Percent of class: 9.9 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 0
	(ii) Shared power to vote or to direct the vote: 3, 632, 371
	(iii) Sole power to dispose or to direct the disposition of: 0
	(iv) Shared power to dispose or to direct the disposition of: 3, 632, 371
Item 5.	Ownership of 5 Percent or Less of a Class.
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Whetstone Capital Advisors, LLC

Signature:	/s/ David Atterbury
Name/Title:	Manager
Date:	09/05/2025

David Atterbury

Signature:	/s/ David Atterbury
Name/Title:	CCO/President
Date:	09/05/2025

FAQ

How many SERA shares does Whetstone Capital Advisors own?

The filing reports 3,632,371 shares, representing 9.9% of Class A common stock.

Does the Schedule 13G indicate Whetstone intends to control Sera Prognostics (SERA)?

No. The filing includes a certification that the shares are not held to change or influence control of the issuer.

What voting power does David Atterbury have over these SERA shares?

The filing shows 0 sole voting power and 3,632,371 shared voting power.

When was the event date and when was the filing signed?

The event date listed is 06/30/2025 and the signatures are dated 09/05/2025.

Under which form was this disclosure filed for SERA?

This disclosure was filed on a Schedule 13G for Class A Common Stock (CUSIP 81749D107).