Centessa (CNTA) Form 144 Discloses Insider Sales and Proposed 7,000-Share Sale

Rhea-AI Filing Summary

Form 144 notice by an insider of Centessa Pharmaceuticals plc (CNTA) reporting a proposed sale of 7,000 common shares through UBS Financial Services with an aggregate market value of $140,000. The filing shows total shares outstanding of 134,073,436, and lists the insider's prior acquisitions: 2,000 founder shares acquired 01/02/2020 and 5,000 shares from an exercise of options on 09/09/2025 (paid in cash). The filing also discloses sales by the same person during the past three months: 15,000 shares on 06/24/2025 for $210,000 and 8,322 shares on 07/29/2025 for $126,750.72. The notice includes the required representation that the seller does not possess undisclosed material adverse information.

Positive

• Regulatory compliance: The filer provided a complete Form 144 notice including broker, quantities, and attestation, supporting market transparency.
• Small relative size: Proposed sale of 7,000 shares represents an immaterial fraction of 134,073,436 shares outstanding.

Negative

• Insider selling activity: The filer sold 15,000 shares on 06/24/2025 and 8,322 shares on 07/29/2025 (total 23,322 shares) and now proposes to sell another 7,000 shares.
• Limited context: The filing contains no operational, financial, or explanatory commentary to clarify reasons for the sales.

Insights

Securities Analyst

TL;DR Insider filed a routine Form 144 proposing a small sale (7,000 shares); prior recent sales totaled 23,322 shares.

The filing is a standard compliance disclosure under Rule 144 showing a proposed brokered sale of 7,000 common shares valued at $140,000 and prior dispositions of 15,000 and 8,322 shares in the past three months. Relative to the issuer's reported 134,073,436 shares outstanding, the proposed sale and recent sales are immaterial on a percentage basis. The form documents acquisition origins (founders' shares and option exercise) and confirms the required attestation regarding undisclosed material information. This is informational for market transparency rather than a standalone material corporate event.

Corporate Governance Expert

TL;DR Disclosure follows regulatory requirements; shows insider liquidity events but no new governance actions.

The document outlines the nature and timing of the insider's holdings and proposed sale, including acquisitions (founders' shares and option exercise) and recent sales with gross proceeds. It fulfills Rule 144 notice obligations and the seller's attestation about material nonpublic information. The filing does not indicate any change in management, board composition, or corporate controls and contains no operational or financial performance data.

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	UBS Financial Services, Inc Eleven Madison Avenue 4th Floor New York NY 10010	7000	140000.00	134073436	09/09/2025	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	01/02/2020	Founders Shares	Issuer			2000	01/02/2020	NA
Common	09/09/2025	Exercise of stock options	Issuer			5000	09/09/2025	Cash

* 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
Mario Alberto Accardi 3RD FLOOR 1 ASHLEY ROAD ALTRINCHAM, CHESHIRE X0 WA14 2DT	Common	06/24/2025	15000	210000.00
Mario Alberto Accardi 3RD FLOOR 1 ASHLEY ROAD ALTRINCHAM, CHESHIRE X0 WA14 2DT	Common	07/29/2025	8322	126750.72

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 does the Form 144 filed for Centessa Pharmaceuticals plc (CNTA) report?

The form reports a proposed sale of 7,000 common shares through UBS with an aggregate market value of $140,000 and lists prior sales and acquisitions.

How many shares outstanding does Centessa report on this Form 144?

The filing lists 134,073,436 shares outstanding.

What prior sales by the same person are disclosed in the past three months?

Sales of 15,000 shares on 06/24/2025 for $210,000 and 8,322 shares on 07/29/2025 for $126,750.72.

What were the acquisition sources for the securities being sold?

The table shows 2,000 founder shares acquired 01/02/2020 from the issuer and 5,000 shares from an option exercise on 09/09/2025 paid in cash.

Does the filing state any undisclosed material information about Centessa?

By signing the notice, the seller represents they do not know any material adverse information that has not been publicly disclosed.