Zura Bio Limited Schedule 13G/A (Amendment No. 3) reports beneficial ownership positions held by Suvretta Capital Management, LLC, Averill Master Fund, Ltd. and Aaron Cowen. The filing shows 9,524,263 shares (9.9%) for Suvretta/Aaron Cowen and 8,372,230 shares (8.8%) for Averill.
The statement discloses that the reported share counts include Class A Ordinary Shares that may be acquired upon exercise of pre-funded warrants with an exercise price of $0.0001, subject to a Maximum Percentage limit (currently 9.99%) and an option for the Fund to increase that cap up to 19.99% (effective after the 61st day following written notice to the issuer). The filing notes the shares are directly owned by advisory clients of Suvretta and that Averill Master Fund, Ltd. is a >5% holder.
Positive
None.
Negative
None.
Insights
Large passive stake reported with capped warrant exercise rights.
The filing documents that Suvretta/Aaron Cowen and Averill Master Fund hold sizeable positions: 9,524,263 shares (9.9%) and 8,372,230 shares (8.8%), respectively. It clarifies that some exposure stems from pre-funded warrants exercisable at $0.0001, limited by a Maximum Percentage cap for Rule 13d-3 purposes.
Key dependencies include the outstanding share count (which affects exercisability) and the Fund's right to raise the cap to 19.99% after a 61-day notice. Subsequent filings may update exercise availability and aggregate percentages.
Key Figures
Suvretta/Aaron Cowen holdings:9,524,263 sharesAverill Master Fund holdings:8,372,230 sharesPre-funded warrant exercise price:$0.0001+2 more
Averill Master Fund holdings8,372,230 sharesreported beneficial ownership, <b>8.8%</b>
Pre-funded warrant exercise price$0.0001exercise price per share for Pre-Funded Warrants
Maximum Percentage (current)9.99%exercise cap for Rule 13d-3 beneficial ownership
Maximum Percentage (possible increase)19.99%cap the Fund may elect to raise to, effective after 61 days' notice
Key Terms
Pre-Funded Warrants, Rule 13d-3, Maximum Percentage
3 terms
Pre-Funded Warrantsfinancial
"Pre-Funded Warrants are only exercisable to the extent that after giving effect to such exercise"
Pre-funded warrants are financial instruments that give investors the right to purchase a company's stock at a set price, but with most or all of the purchase price paid upfront. They function like a coupon or gift card for stock, allowing investors to buy shares later at a fixed price, which can be beneficial if they want to avoid future price increases. This makes them important for investors seeking flexibility and certainty in their investment plans.
Rule 13d-3regulatory
"for purposes of Rule 13d-3 under the Exchange Act"
Rule 13d-3 defines who is treated as the beneficial owner of a company’s shares for U.S. securities disclosure rules — essentially anyone who has the power to vote or direct how shares are voted, or the power to buy or sell them, even if they don’t hold the certificates. For investors this matters because crossing certain ownership thresholds triggers public filing and disclosure obligations and signals potential control or influence, much like having the keys to a car implies you can drive it even if it’s registered to someone else.
Maximum Percentageregulatory
"the "Maximum Percentage" of the outstanding Class A Ordinary Shares"
Suvretta Capital Management reports beneficial ownership of 9,524,263 Class A Ordinary Shares (9.9%). The figure includes shares issuable upon exercise of pre-funded warrants subject to a Maximum Percentage limit for Rule 13d-3 computations.
How many shares does Averill Master Fund hold in ZURA?
Averill Master Fund, Ltd. reports ownership of 8,372,230 Class A Ordinary Shares (8.8%). These shares are directly owned by the Fund and are reported separately from other advisory clients of Suvretta.
What are the terms of the pre-funded warrants noted in the filing?
The pre-funded warrants have an exercise price of $0.0001 per share and no expiration date. Their exercisability is limited so holders would not beneficially own more than a stated Maximum Percentage under Rule 13d-3.
What is the "Maximum Percentage" and can it change?
The filing states a Maximum Percentage of 9.99% that limits warrant exercises for Rule 13d-3 purposes. By written notice the Fund may increase the cap to up to 19.99%, effective on the 61st day after notice is delivered.
Who legally owns the reported securities?
The securities are directly owned by advisory clients of Suvretta Capital Management, LLC. Averill Master Fund, Ltd. is specifically identified as a >5% holder; other advisory clients are reported as holding less than 5% each.
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No. 3)
Zura Bio Limited
(Name of Issuer)
Class A Ordinary Shares, par value $0.0001 per share
(Title of Class of Securities)
G9TY5A101
(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):
G9TY5A101
1
Names of Reporting Persons
Suvretta Capital Management, 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
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
9,524,263.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
9,524,263.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
9,524,263.00
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 Number(s):
G9TY5A101
1
Names of Reporting Persons
Averill Master Fund, Ltd.
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
CAYMAN ISLANDS
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
8,372,230.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
8,372,230.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
8,372,230.00
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)
8.8 %
12
Type of Reporting Person (See Instructions)
CO
SCHEDULE 13G
CUSIP Number(s):
G9TY5A101
1
Names of Reporting Persons
Aaron Cowen
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
9,524,263.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
9,524,263.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
9,524,263.00
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:
Zura Bio Limited
(b)
Address of issuer's principal executive offices:
1489 W. Warm Springs Rd. #110 Henderson, Nevada 89014
Item 2.
(a)
Name of person filing:
Suvretta Capital Management, LLC - Delaware
Averill Master Fund, Ltd. - Cayman Islands
Aaron Cowen - United States
(b)
Address or principal business office or, if none, residence:
Suvretta Capital Management, LLC:
540 Madison Avenue, 7th Floor
New York, New York 10022
United States of America
Averill Master Fund, Ltd.:
c/o Maples Corporate Services Limited
P.O. Box 309
Ugland House
Grand Cayman KY1-1104
Cayman Islands
Aaron Cowen:
c/o Suvretta Capital Management, LLC
540 Madison Avenue, 7th Floor
New York, New York 10022
(c)
Citizenship:
(d)
Title of class of securities:
Class A Ordinary Shares, par value $0.0001 per share
(e)
CUSIP No.:
G9TY5A101
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:
Items 6 through 9 and 11 of each of the cover pages to this Schedule 13G are incorporated herein by reference. Set forth below is the aggregate number of shares of Class A Ordinary Shares directly held by Averill Master Fund, Ltd. (the "Fund"), which may be deemed to be indirectly beneficially owned by Suvretta Capital Management, LLC and Aaron Cowen, as well as Class A Ordinary Shares that may be acquired upon the exercise of pre-funded warrants with no expiration date with an exercise price of $0.0001 per share of Class A Ordinary Shares ("Pre-Funded Warrants"), subject to the limitations on exercise described below.
The Pre-Funded Warrants are only exercisable to the extent that after giving effect to such exercise the holders thereof, their affiliates and any persons who are members of a Section 13(d) group with the holders or their affiliates would beneficially own in the aggregate, for purposes of Rule 13d-3 under the Exchange Act, no more than 9.99% of the outstanding Class A Ordinary Shares (the "Maximum Percentage"). By written notice to the Issuer, the Fund may from time to time increase or decrease the Maximum Percentage applicable to it to any other percentage not in excess of 19.99%, provided that any such increase will not be effective until the sixty-first (61st) day after such notice is delivered to the Issuer. As a result of this restriction, the Pre-Funded Warrants are not all presently exercisable and the number of shares of Class A Ordinary Shares that may be issued upon exercise of the Pre-Funded Warrants by the above holders may change depending upon changes in the outstanding Class A Ordinary Shares.
Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1. For computations regarding securities which represent a right to acquire an underlying security see ss. 240.13d-3(d)(1).
Suvretta Capital Management, LLC - 9,524,263
Averill Master Fund, Ltd. - 8,372,230
Aaron Cowen - 9,524,263
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.
All of the securities reported in this Schedule 13G Amendment No. 3 are directly owned by advisory clients of Suvretta Capital Management, LLC. None of those advisory clients, other than Averill Master Fund, Ltd., may be deemed to beneficially own more than 5% of the Class A Ordinary Shares, par value $0.0001 per share.
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary.
See Exhibit B attached hereto.
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.
Suvretta Capital Management, LLC
Signature:
/s/ Andrew Nathanson
Name/Title:
Andrew Nathanson, General Counsel and Chief Compliance Officer
Date:
05/12/2026
Averill Master Fund, Ltd.
Signature:
/s/ Andrew Nathanson
Name/Title:
Andrew Nathanson, Authorized Signatory
Date:
05/12/2026
Aaron Cowen
Signature:
/s/ Aaron Cowen
Name/Title:
Aaron Cowen
Date:
05/12/2026
Comments accompanying signature: * Each Reporting Person disclaims beneficial ownership of the reported securities except to the extent of his, her or its pecuniary interest therein, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.
To the extent that "ownership of 5 percent or less of a class" was indicated in Item 5, such response only applies to the Reporting Person(s) that indicated elsewhere herein that it beneficially owns five percent (5%) or less of the class.
Exhibit Information
Exhibit A - Joint Filing Agreement
Exhibit B - Control Person Identification
