Centessa Pharmaceuticals insider plans 55k-share June sale via Form 144

Rhea-AI Filing Summary

Centessa Pharmaceuticals plc (CNTA) – Form 144 filing overview

An affiliate identified as Saurabh Saha has notified the SEC of an intent to sell 55,000 common shares through UBS Financial Services on or about 20 June 2025. The filing quotes an aggregate market value of $707,575.

The issuer reports 133,618,774 shares outstanding; the proposed sale therefore represents roughly 0.04 % of the float, well below Rule 144’s 1 % ceiling. The shares were obtained the same day (20 Jun 2025) via a cash exercise of stock options.

Recent trading history: the same seller executed four transactions in the past three months, disposing of a total of 165,000 shares for gross proceeds of $2.30 million on 20 Mar, 21 Apr, 22 Apr and 20 May 2025. No 10b5-1 plan date or explanatory remarks were supplied.

Investor take-away: While the volume is immaterial to Centessa’s capital structure, consecutive insider sales may attract scrutiny as a potential sentiment indicator. The filing expressly states that the seller is not aware of undisclosed material information, but it offers no context regarding the rationale for continued sales.

Positive

• None.

Negative

• Continued insider selling: Proposed sale of 55,000 shares follows 165,000 shares already sold in the prior 3 months, potentially signaling negative insider sentiment.

Insights

Financial Analyst

TL;DR: 55k-share Form 144 adds to 165k earlier sales; negligible dilution, but sustained insider selling could weigh on sentiment.

The new notice covers 55,000 shares (≈0.04 % of outstanding) valued at $707k, following $2.3 m of stock sold since March. From a balance-sheet perspective the transaction is immaterial and creates no dilution because shares were already outstanding. However, repeated insider monetisation within a short window can foster bearish interpretations among momentum traders and governance-focused funds, particularly absent a disclosed 10b5-1 plan. Volume remains far under Rule 144 limits, so regulatory risk is minimal. Overall market impact is likely modest, yet optics skew cautiously negative.

Corporate Governance Expert

TL;DR: Routine Rule 144 filing; pattern of insider disposals merits monitoring but no compliance red flags.

The filing satisfies technical Rule 144 disclosure: share count, broker, acquisition method and prior-90-day sales are all provided. With sales well inside the 1 %/4-week threshold, there is no exemption overrun. Absence of a stated 10b5-1 plan may limit safe-harbor defenses if trading occurs amid undisclosed events, yet the standard certification is present. Governance committees and investors should log the cumulative 220k shares earmarked/sold in 2025 for trend analysis, but no immediate governance violations are evident.

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

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 1000 Harbor Blvd 3rd Floor Weehawken NJ 07086	55000	707575.00	133618774	06/20/2025	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	06/20/2025	Exercise of Stock Options	Issuer			55000	06/20/2025	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
Saurabh Saha 3RD FLOOR 1 ASHLEY ROAD ALTRINCHAM, CHESHIRE X0 WA14 2D	Common	03/20/2025	55000	918060.00
Saurabh Saha 3RD FLOOR 1 ASHLEY ROAD ALTRINCHAM, CHESHIRE X0 WA14 2DT	Common	04/21/2025	14656	180100.26
Saurabh Saha 3RD FLOOR 1 ASHLEY ROAD ALTRINCHAM, CHESHIRE X0 WA14 2D	Common	04/22/2025	40344	501475.92
Saurabh Saha 3RD FLOOR 1 ASHLEY ROAD ALTRINCHAM, CHESHIRE X0 WA14 2DT	Common	05/20/2025	55000	699110.50

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

How many Centessa (CNTA) shares are covered by the new Form 144?

The notice covers 55,000 common shares.

What is the estimated value of the shares to be sold?

The filing lists an aggregate market value of $707,575 for the 55,000 shares.

When is the anticipated sale date for the shares?

The approximate sale date disclosed is 20 June 2025.

How many Centessa shares has the filer sold in the last three months?

The filer previously sold 165,000 shares between 20 March and 20 May 2025.

What percentage of Centessa’s outstanding shares does the proposed sale represent?

About 0.04 % of the company’s 133,618,774 outstanding shares.