Affinity Asset Advisors (NASDAQ: STRO) discloses 8.8% Sutro Biopharma stake

Rhea-AI Filing Summary

Affinity Asset Advisors, LLC and its managing member Michael Cho report beneficial ownership of 748,382 shares of Sutro Biopharma, Inc. common stock, equal to approximately 8.8% of the company’s outstanding shares based on 8,519,392 shares outstanding as of December 3, 2025.

The shares are held by Affinity Healthcare Fund, LP, for which Affinity Asset Advisors serves as investment manager. As of the current reporting date, the reporting persons have sole voting and dispositive power over these shares and certify that the position is held in the ordinary course of business, without the purpose or effect of changing or influencing control of Sutro Biopharma.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 1)

Sutro Biopharma, Inc.

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

869367201

(CUSIP Number)

01/22/2026

(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)

SCHEDULE 13G

CUSIP No. 869367201

1

Names of Reporting Persons

Affinity Asset Advisors, 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 748,382.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 748,382.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

748,382.00

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)

IA, OO

SCHEDULE 13G

CUSIP No. 869367201

1

Names of Reporting Persons

Michael Cho

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 748,382.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 748,382.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

748,382.00

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)

IN, HC

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Sutro Biopharma, Inc.
(b)	Address of issuer's principal executive offices: 111 Oyster Point Blvd., South San Franciso, California, 94080
Item 2.
(a)	Name of person filing: Affinity Asset Advisors, LLC Michael Cho
(b)	Address or principal business office or, if none, residence: 450 Park Avenue Suite 1403 New York, NY 10022
(c)	Citizenship: Affinity Asset Advisors, LLC is a Delaware limited liability company, and Michael Cho is an individual and is a citizen of the United States.
(d)	Title of class of securities: Common Stock, $0.001 par value per share
(e)	CUSIP No.: 869367201
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 securities reported herein are directly held by Affinity Healthcare Fund, LP (the "Fund"). Affinity Asset Advisors, LLC (the "Adviser") is the investment manager of the Fund and exercises voting and investment power over the securities held directly by the Fund reported herein pursuant to an investment management agreement between the Adviser, the Fund, and the general partner of the Fund. The Adviser may be deemed to beneficially own the securities reported herein held by the Fund by virtue of its position as investment manager of the Fund. Michael Cho, the managing member of the Adviser, may be deemed a beneficial owner of the securities reported herein held directly by the Fund. As of the date hereof, the Adviser and Mr. Cho (collectively, the "Reporting Persons") beneficially own 748,382 shares of common stock, par value $0.001 per share ("Common Stock"), of Sutro Biopharma, Inc. (the "Issuer"). As of December 31, 2025, the Fund and the Adviser beneficially owned 748,382 shares of Common Stock.
(b)	Percent of class: As of the date hereof, the Reporting Persons beneficially own approximately 8.8% of the Common Stock outstanding. As of December 31, 2025, the Fund and the Adviser beneficially owned approximately 8.8% of the Common Stock outstanding. The percentages disclosed above are based on 8,519,392 shares of Common Stock of the Issuer outstanding as of December 3, 2025, as set forth in the Issuer's Form 8-K filed with the Securities and Exchange Commission on December 3, 2025.
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: As of the date hereof, the Reporting Persons have sole power to vote or to direct the vote of 748,382 shares of Common Stock. As of December 31, 2025, the Fund and the Adviser had sole power to vote or to direct the vote of 0 shares of Common Stock.
	(ii) Shared power to vote or to direct the vote: As of the date hereof, the Reporting Persons have shared power to vote or to direct the vote of 0 shares of Common Stock. As of December 31, 2025, the Fund and the Adviser had shared power to vote or to direct the vote of 748,382 shares of Common Stock.
	(iii) Sole power to dispose or to direct the disposition of: As of the date hereof, the Reporting Persons have sole power to dispose or to direct the disposition of 748,382 shares of Common Stock. As of December 31, 2025, the Fund and the Adviser had sole power to dispose or to direct the disposition of 0 shares of Common Stock.
	(iv) Shared power to dispose or to direct the disposition of: As of the date hereof, the Reporting Persons have shared power to dispose or to direct the disposition of 0 shares of Common Stock. As of December 31, 2025, the Fund and the Adviser had shared power to dispose or to direct the disposition of 748,382 shares of Common Stock.
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.
	Not Applicable
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.

Affinity Asset Advisors, LLC

Signature:	/s/ Andrew Weinstein
Name/Title:	Andrew Weinstein, Chief Financial Officer and Chief Compliance Officer
Date:	01/29/2026

Michael Cho

Signature:	/s/ Michael Cho
Name/Title:	Michael Cho, Self
Date:	01/29/2026

FAQ

What stake does Affinity Asset Advisors report in Sutro Biopharma (STRO)?

Affinity Asset Advisors reports beneficial ownership of 748,382 Sutro Biopharma shares, representing approximately 8.8% of the common stock outstanding. This position is disclosed on a Schedule 13G/A and reflects a significant institutional stake in the company.

Who are the reporting persons in this Sutro Biopharma (STRO) Schedule 13G/A?

The reporting persons are Affinity Asset Advisors, LLC and its managing member, Michael Cho. The shares are directly held by Affinity Healthcare Fund, LP, with Affinity Asset Advisors acting as investment manager and exercising voting and investment power over the position.

How many Sutro Biopharma (STRO) shares are beneficially owned and what percentage is this?

The filing states beneficial ownership of 748,382 shares of Sutro Biopharma common stock, which equals approximately 8.8% of the company’s outstanding shares. The percentage is calculated using 8,519,392 shares outstanding as of December 3, 2025.

How is voting and dispositive power over Sutro Biopharma (STRO) shares allocated?

As of the reporting date, the filing states the reporting persons have sole power to vote and dispose of 748,382 Sutro Biopharma shares. Earlier, as of December 31, 2025, these powers were reported as shared, indicating a change in how authority over the shares is structured.

Is Affinity Asset Advisors seeking control of Sutro Biopharma (STRO)?

The certification states the securities were acquired and are held in the ordinary course of business and not for the purpose or effect of changing or influencing control of Sutro Biopharma. The position is not reported as part of any control-seeking transaction or group.

Which entity actually holds the Sutro Biopharma (STRO) shares reported on the 13G/A?

The filing explains that the 748,382 shares are directly held by Affinity Healthcare Fund, LP. Affinity Asset Advisors, LLC is the investment manager for this fund and may be deemed to beneficially own the shares through its management role, with Michael Cho as managing member.