Centessa Pharmaceuticals plc Schedule 13G: Pentwater Capital Management and Matthew Halbower report shared beneficial ownership of 8,170,000 ADSs, representing 5.3% of the Ordinary Shares based on 154,568,531 shares outstanding as of March 17, 2026.
The filing states the ADSs are represented by CUSIP 152309100, that each ADS represents one Ordinary Share, and that the Pentwater Funds have the right to receive dividends or sale proceeds. The statement is a joint filing by the Investment Manager and Mr. Halbower.
Positive
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Negative
None.
Insights
Pentwater reports a 5.3% shared stake via 8,170,000 ADSs.
Pentwater Capital Management and Mr. Matthew Halbower jointly report shared voting and dispositive power over 8,170,000 ADSs, equal to 5.3% of the class using an outstanding base of March 17, 2026. The filing cites CUSIP 152309100 and confirms each ADS equals one Ordinary Share.
Holding level and the statement that the Pentwater Funds ‘‘have the right to receive or the power to direct the receipt of dividends’’ are factual disclosures; cash‑flow treatment and any planned transactions are not provided in the excerpt.
Joint filing clarifies shared control, not sole beneficial ownership.
The cover data shows 0 sole voting/dispositive power and 8,170,000 in shared voting/dispositive power for the reporting parties. The document explicitly notes the filing should not be construed as an admission of beneficial ownership under Section 13.
Signatures indicate a joint filing arrangement; subsequent filings would be required to show any change in voting or disposition intent.
Key Figures
ADSs reported:8,170,000 ADSsPercent of class:5.3%Shares outstanding:154,568,531 shares+1 more
4 metrics
ADSs reported8,170,000 ADSsshared voting/dispositive power reported on cover page
Percent of class5.3%based on outstanding shares as of <date>March 17, 2026</date>
Shares outstanding154,568,531 sharesoutstanding as of <date>March 17, 2026</date>
CUSIP152309100CUSIP assigned to the ADSs quoted on Nasdaq
"Represented by 8,170,000 ADSs (as defined in Item 2(a))."
Schedule 13Gregulatory
"Item 1. (a) Name of issuer: Centessa Pharmaceuticals plc"
A Schedule 13G is a formal document that investors file with the government when they acquire a large ownership stake in a company, usually for investment purposes rather than control. It helps keep the public informed about who owns significant parts of a company's shares, which can influence how the company is managed and how investors make decisions. Filing this schedule is important for transparency and understanding the ownership landscape of publicly traded companies.
Shared dispositive powerregulatory
"Shared Dispositive Power 8,170,000.00"
Beneficial ownershipregulatory
"Amount beneficially owned: The information required by Item 4(a) is set forth in Row 9"
Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
Centessa Pharmaceuticals plc
(Name of Issuer)
Ordinary Shares, nominal value GBP 0.002 per share
(Title of Class of Securities)
152309100
(CUSIP Number)
03/31/2026
(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)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
152309100
1
Names of Reporting Persons
Pentwater Capital Management LP
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
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
8,170,000.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
8,170,000.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
8,170,000.00
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)
5.3 %
12
Type of Reporting Person (See Instructions)
IA, PN
Comment for Type of Reporting Person: Represented by 8,170,000 ADSs (as defined in Item 2(a)).
SCHEDULE 13G
CUSIP Number(s):
152309100
1
Names of Reporting Persons
Matthew Halbower
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
8,170,000.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
8,170,000.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
8,170,000.00
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)
5.3 %
12
Type of Reporting Person (See Instructions)
HC, IN
Comment for Type of Reporting Person: Represented by 8,170,000 ADSs.
This statement is filed by:
(i) Pentwater Capital Management LP (the "Investment Manager"), a Delaware limited partnership, and the investment adviser to certain funds (the "Pentwater Funds"), with respect to the ordinary shares, nominal value GBP 0.002 per share ("Ordinary Shares"), of Centessa Pharmaceuticals plc, a public limited liability company incorporated under the laws of England and Wales (the "Company"), represented by ADSs (as defined below) directly held by the Pentwater Funds; and
(ii) Mr. Matthew Halbower ("Mr. Halbower"), the sole shareholder of MCH PWCM Holdings Inc., the general partner of the Investment Manager, with respect to the Ordinary Shares, represented by ADSs, directly held by the Pentwater Funds.
The foregoing persons are hereinafter sometimes collectively referred to as the "Reporting Persons."
The filing of this statement should not be construed as an admission that any of the foregoing persons or any Reporting Person is, for the purposes of Section 13 of the Securities and Exchange Act of 1934, the beneficial owner of the securities reported herein.
There is no CUSIP assigned to the Ordinary Shares. The CUSIP number 152309100 has been assigned to the American Depositary Shares ("ADSs") of the Company, which are quoted on the Nasdaq Global Select Market under the symbol "CNTA." Each ADS represents one Ordinary Share.
(b)
Address or principal business office or, if none, residence:
The address of the business office of each of the Reporting Persons is 1001 10th Avenue South, Suite 216, Naples, FL 34102.
(c)
Citizenship:
The Investment Manager is a Delaware limited partnership. Mr. Halbower is a citizen of the United States.
(d)
Title of class of securities:
Ordinary Shares, nominal value GBP 0.002 per share
(e)
CUSIP Number(s):
152309100
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:
The information required by Item 4(a) is set forth in Row 9 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
The percentage set forth in this Schedule 13G is calculated based upon an aggregate of 154,568,531 Ordinary Shares outstanding as of March 17, 2026, as reported in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2025, filed with the Securities and Exchange Commission on March 31, 2026.
(b)
Percent of class:
5.3%
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
The information required by Item 4(c)(i) is set forth in Row 5 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
(ii) Shared power to vote or to direct the vote:
The information required by Item 4(c)(ii) is set forth in Row 6 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
(iii) Sole power to dispose or to direct the disposition of:
The information required by Item 4(c)(iii) is set forth in Row 7 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
(iv) Shared power to dispose or to direct the disposition of:
The information required by Item 4(c)(iv) is set forth in Row 8 of the cover page for each of the Reporting Persons and is incorporated herein by reference.
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.
See Item 2(a). The Pentwater Funds have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the Ordinary Shares reported herein.
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 acquired and are held in the ordinary course of business and 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.
Pentwater Capital Management LP
Signature:
/s/ Matthew Halbower
Name/Title:
By: MCH PWCM Holdings Inc., General Partner, By: Matthew Halbower, Chief Executive Officer
What stake does Pentwater report in Centessa (CNTA)?
Pentwater reports shared beneficial ownership of 8,170,000 ADSs, equal to 5.3% of the Ordinary Shares based on 154,568,531 shares outstanding as of March 17, 2026. The ADSs carry CUSIP 152309100.
Do the filing parties have sole voting power over CNTA shares?
No. The cover data shows 0 sole voting power and 8,170,000 in shared voting power. The filing reports shared voting and dispositive authority rather than sole control.
How does the filing treat ADSs versus Ordinary Shares for CNTA?
The filing states each ADS represents one Ordinary Share. It uses the ADS CUSIP 152309100 and reports holdings in ADSs that represent Ordinary Shares on a one‑for‑one basis.
Who filed the Schedule 13G for Centessa (CNTA)?
This is a joint filing by Pentwater Capital Management LP (the investment manager to certain Pentwater Funds) and Matthew Halbower, who is identified in the filing as the sole shareholder of the general partner of the Investment Manager.
Does the Schedule 13G disclose planned sales or purchases of CNTA shares?
No. The filing discloses current shared ownership and that the Pentwater Funds have rights to dividends or sale proceeds but does not state any planned purchases or dispositions in the provided excerpt.
