Lewis T. "rusty" Williams - 17 Feb 2026 Form 4 Insider Report for Protagonist Therapeutics, Inc (PTGX)

Reporting relationship: Director
Issuer ticker: PTGX
Reported as of: 17 Feb 2026
Net transaction value: -$1,288,440
SEC form: 4
Accepted by SEC: 18 Feb 2026, 18:12:56 UTC
Prior SEC filing: 06 Jan 2026
Source filing: View source filing
Reporting owner signature: /s/ Matthew Gosling, Attorney-in-Fact for Lewis T. "Rusty" Williams

Key filing fact

Lewis T. "rusty" Williams filed Form 4 for Protagonist Therapeutics, Inc (PTGX) on 18 Feb 2026.

Key facts

This page summarizes Lewis T. "rusty" Williams's Form 4 filing for Protagonist Therapeutics, Inc (PTGX).
3 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 18 Feb 2026, 18:12.

Change

Previous filing in this sequence was filed on 06 Jan 2026.
Current net transaction value: -$1,288,440.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001475714 Primary reporting owner

Williams Lewis T

Relationship: Director
Address: C/O PROTAGONIST THERAPEUTICS, INC., 7707 GATEWAY BLVD., SUITE 140, NEWARK
Signature: /s/ Matthew Gosling, Attorney-in-Fact for Lewis T. "Rusty" Williams
Signature date: 18 Feb 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

PTGX transaction

Common Stock

Options Exercise

Transaction value: $195,120
Shares: +18,000
Change %: +230%
Price: $10.84
Shares after: 25,825
Date: 17 Feb 2026
Ownership: Direct

PTGX transaction

Common Stock

Sale

Transaction value: $1,483,560
Shares: -18,000
Change %: -70%
Price: $82.42
Shares after: 7,825
Date: 17 Feb 2026
Ownership: Direct
Footnotes: F1

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

PTGX transaction Derivative

Stock Option (right to buy)

Options Exercise

Transaction value: $0
Shares: +18,000
Change %
Price: $0.000000
Shares after: 6,000
Date: 17 Feb 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 18,000
Exercise price: $10.84
Footnotes: F2

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 2 footnotes

Footnote F1

The price reported represents the weighted average sale price per share. The shares were sold in multiple transactions at prices ranging from $81.47 to $83.12. Upon request by the staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder of the Issuer, the Reporting Person will provide full information regarding the number of shares sold at each separate price.

Footnote F2

These stock options are fully vested.