[144] SERA PROGNOSTICS, INC. SEC Filing

Rhea-AI Filing Summary

Sera Prognostics, Inc. insider Robert Gardner Harrison filed a Notice of Proposed Sale under Rule 144 reporting the planned sale of 2,000 common shares through Morgan Stanley Smith Barney LLC on 10/07/2025 with an aggregate market value of $6,520.00. The filing shows those 2,000 shares were acquired as Restricted Stock Units on 02/06/2024 and lists prior sales by the same person during the past three months totaling 14,607 shares across multiple transactions (largest listed: 6,000 on 08/20/2025 for $13,290.00). The filer certifies no undisclosed material adverse information and references reliance on Rule 10b5-1 timing where applicable.

Positive

• Planned sale is modest at 2,000 shares with $6,520.00 aggregate value
• Acquisition source is disclosed as Restricted Stock Units dated 02/06/2024, showing these are compensation-related shares

Negative

• Significant recent insider selling totaled 14,607 shares in the past three months, which could increase share supply
• Multiple sales used a 10b5-1 plan, requiring confirmation of plan adoption dates to fully assess compliance timing

Insights

Insider Transactions Compliance Analyst

TL;DR: Reported insider stock sales are routine, tied to RSU vesting and prior 10b5-1 plan activity.

The filing records a planned sale of 2,000 shares acquired as Restricted Stock Units on 02/06/2024, to be executed via Morgan Stanley Smith Barney LLC on 10/07/2025 at a reported aggregate value of $6,520.00. Multiple prior sales in the past three months are disclosed, including 6,000 shares on 08/20/2025 and 2,000 via a 10b5-1 plan on 09/09/2025, indicating systematic sales rather than a single large disposition.

Compliance risk depends on whether the sales match documented 10b5-1 plan dates and trading-window rules; the filer affirms no undisclosed material information. Investors can monitor the timing of any stated plan adoption date and subsequent filings to confirm adherence to scheduled plan parameters.

Corporate Insider Activity Analyst

TL;DR: Insider sold material share blocks recently; cumulative recent sales exceed single planned sale.

The disclosed recent activity shows cumulative sales of 14,607 shares over the last three months, with gross proceeds reported (examples: $13,290.00 for 6,000 shares on 08/20/2025). The planned 2,000-share sale is smaller than some prior transactions but continues an observable pattern of disposals.

This pattern may modestly affect free float and near-term share supply; track future Form 4 or Form 144 filings to see if sales persist or slow after the listed 10/07/2025.

Form 144 Filer Information	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 144 NOTICE OF PROPOSED SALE OF SECURITIES PURSUANT TO RULE 144 UNDER THE SECURITIES ACT OF 1933
FORM 144

144: Filer Information

Filer CIK
Filer CCC
Is this a LIVE or TEST Filing?	LIVE TEST
Submission Contact Information
Name
Phone
E-Mail Address

144: Issuer Information

Name of Issuer

SEC File Number

Address of Issuer

Phone

Name of Person for Whose Account the Securities are To Be Sold

See the definition of "person" in paragraph (a) of Rule 144. Information is to be given not only as to the person for whose account the securities are to be sold but also as to all other persons included in that definition. In addition, information shall be given as to sales by all persons whose sales are required by paragraph (e) of Rule 144 to be aggregated with sales for the account of the person filing this notice.

Relationship to Issuer

144: Securities Information

Title of the Class of Securities To Be Sold	Name and Address of the Broker	Number of Shares or Other Units To Be Sold	Aggregate Market Value	Number of Shares or Other Units Outstanding	Approximate Date of Sale	Name the Securities Exchange
Common	Morgan Stanley Smith Barney LLC Executive Financial Services 1 New York Plaza 8th Floor New York NY 10004	2000	6520.00	37094109	10/07/2025	NASDAQ

Furnish the following information with respect to the acquisition of the securities to be sold and with respect to the payment of all or any part of the purchase price or other consideration therefor:

144: Securities To Be Sold

Title of the Class	Date you Acquired	Nature of Acquisition Transaction	Name of Person from Whom Acquired	Is this a Gift?	Date Donor Acquired	Amount of Securities Acquired	Date of Payment	Nature of Payment *
Common	02/06/2024	Restricted Stock Units	Issuer			2000	02/06/2024	N/A

* If the securities were purchased and full payment therefor was not made in cash at the time of purchase, explain in the table or in a note thereto the nature of the consideration given. If the consideration consisted of any note or other obligation, or if payment was made in installments describe the arrangement and state when the note or other obligation was discharged in full or the last installment paid.

Furnish the following information as to all securities of the issuer sold during the past 3 months by the person for whose account the securities are to be sold.

144: Securities Sold During The Past 3 Months

Name and Address of Seller	Title of Securities Sold	Date of Sale	Amount of Securities Sold	Gross Proceeds
ROBERT GARDNER HARRISON 2749 East Parleys Way, Suite 200 Salt Lake City UT 84109	Common	09/11/2025	645	2018.85
10b5-1 Sales for ROBERT GARDNER HARRISON 2749 East Parleys Way, Suite 200 Salt Lake City UT 84109	Common	09/09/2025	2000	6107.60
10b5-1 Sales for ROBERT GARDNER HARRISON 2749 East Parleys Way, Suite 200 Salt Lake City UT 84109	Common	08/20/2025	6000	13290.00
ROBERT GARDNER HARRISON 2749 East Parleys Way, Suite 200 Salt Lake City UT 84109	Common	08/08/2025	5962	15143.48

144: Remarks and Signature

Remarks

Date of Notice

Date of Plan Adoption or Giving of Instruction, If Relying on Rule 10b5-1

ATTENTION:

The person for whose account the securities to which this notice relates are to be sold hereby represents by signing this notice that he does not know any material adverse information in regard to the current and prospective operations of the Issuer of the securities to be sold which has not been publicly disclosed. If such person has adopted a written trading plan or given trading instructions to satisfy Rule 10b5-1 under the Exchange Act, by signing the form and indicating the date that the plan was adopted or the instruction given, that person makes such representation as of the plan adoption or instruction date.

Signature

ATTENTION: Intentional misstatements or omission of facts constitute Federal Criminal Violations (See 18 U.S.C. 1001)

FAQ

What did SERA insider Robert Gardner Harrison file on Form 144?

The filing notifies a proposed sale of 2,000 common shares via Morgan Stanley Smith Barney LLC on 10/07/2025 with aggregate market value $6,520.00.

When were the shares to be sold by the SERA insider acquired?

The 2,000 shares were acquired as Restricted Stock Units on 02/06/2024.

Has the SERA insider sold shares recently?

Yes; the filing lists sales in the past three months totaling 14,607 shares, including 6,000 shares on 08/20/2025 for $13,290.00 and 2,000 shares on 09/09/2025 under a 10b5-1 plan.

Does the Form 144 state whether a 10b5-1 plan was used?

Yes; some transactions are labeled as 10b5-1 Sales, and the filer references plan adoption or instruction dates in the remarks section without listing the specific plan adoption date.

What representation does the filer make in the Form 144?

The filer represents by signature that they do not possess any undisclosed material adverse information about the issuer as of the plan adoption or instruction date.