Vanguard reports 8.65% PTGX stake in Protagonist Therapeutics (NASDAQ: PTGX)

Rhea-AI Filing Summary

The Vanguard Group filed an amended Schedule 13G reporting beneficial ownership of 5,413,690 shares of Protagonist Therapeutics Inc common stock, representing 8.65% of the class as of 12/31/2025.

Vanguard reports shared voting power over 473,004 shares and shared dispositive power over 5,413,690 shares, with no sole voting or dispositive power. The securities are held in the ordinary course of business, and Vanguard states they were not acquired to change or influence control of Protagonist. Vanguard also notes an internal realignment effective January 12, 2026, after which certain subsidiaries may report beneficial ownership separately.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 4)

Protagonist Therapeutics Inc

(Name of Issuer)

Common Stock

(Title of Class of Securities)

74366E102

(CUSIP Number)

12/31/2025

(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. 74366E102

1

Names of Reporting Persons

The Vanguard Group

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

PENNSYLVANIA

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 473,004.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 5,413,690.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

5,413,690.00

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)

8.65 %

12

Type of Reporting Person (See Instructions)

IA

Comment for Type of Reporting Person: On January 12, 2026, The Vanguard Group, Inc. went through an internal realignment. As of that date, The Vanguard Group, Inc. no longer performs portfolio management services or administers proxy voting. In accordance with SEC Release No. 34-39538 (January 12, 1998), The Vanguard Group, Inc. anticipates that certain subsidiaries or business divisions of subsidiaries of The Vanguard Group, Inc., that currently have, or are deemed to have, beneficial ownership with The Vanguard Group, Inc., will report beneficial ownership separately (on a disaggregated basis) from The Vanguard Group, Inc. in reliance on such release. These subsidiaries and/or business divisions pursue the same investment strategies as previously pursued by The Vanguard Group, Inc. prior to the realignment.

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Protagonist Therapeutics Inc
(b)	Address of issuer's principal executive offices: 7707 Gateway Blvd, Suite 140, Newark, CA, 94560
Item 2.
(a)	Name of person filing: The Vanguard Group
(b)	Address or principal business office or, if none, residence: 100 Vanguard Blvd., Malvern, PA 19355
(c)	Citizenship: PA
(d)	Title of class of securities: Common Stock
(e)	CUSIP No.: 74366E102
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: 5413690
(b)	Percent of class: 8.65 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 0
	(ii) Shared power to vote or to direct the vote: 473004
	(iii) Sole power to dispose or to direct the disposition of: 0
	(iv) Shared power to dispose or to direct the disposition of: 5413690
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. The Vanguard Group, Inc.'s clients, including investment companies registered under the Investment Company Act of 1940 and other managed accounts, have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the securities reported herein. No one other person's interest in the securities reported herein is more than 5%.
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.

The Vanguard Group

Signature:	Ashley Grim
Name/Title:	Head of Global Fund Administration
Date:	01/30/2026

FAQ

What ownership stake does The Vanguard Group report in PTGX?

The Vanguard Group reports beneficial ownership of 5,413,690 Protagonist Therapeutics (PTGX) common shares, representing 8.65% of the outstanding class as of December 31, 2025. This filing is made on an amended Schedule 13G, indicating a passive, non‑control investment position.

Does The Vanguard Group seek to influence control of Protagonist Therapeutics (PTGX)?

The Vanguard Group states the Protagonist Therapeutics shares were acquired and are held in the ordinary course of business, not to change or influence control of the issuer. The filing confirms the holdings are not part of any control-related transaction or activist campaign.

How much voting power does Vanguard have over PTGX shares?

Vanguard reports shared voting power over 473,004 Protagonist Therapeutics shares and no sole voting power. It also discloses shared dispositive power over 5,413,690 shares, meaning voting influence is limited and largely tied to specific accounts rather than unilateral control over the entire position.

Who ultimately benefits from Vanguard’s PTGX holdings?

The filing explains that Vanguard’s clients, including registered investment companies and other managed accounts, have rights to dividends and sale proceeds from the Protagonist shares. No single other person’s interest in these securities exceeds 5% of the class, according to the disclosure.

What internal changes at Vanguard are mentioned in the PTGX filing?

Vanguard notes an internal realignment effective January 12, 2026, after which it no longer performs portfolio management or proxy voting. Certain subsidiaries or business divisions are expected to report beneficial ownership separately, while continuing the same investment strategies previously pursued by The Vanguard Group.

What type of filing did The Vanguard Group submit for PTGX?

The Vanguard Group submitted an Amendment No. 4 to Schedule 13G for Protagonist Therapeutics common stock. Schedule 13G is used by passive investors holding more than 5% of a company’s shares, indicating a non‑activist, non‑control investment position in the issuer.