SEC Form 4 · accession 0001104659-26-106831

Protagonist Therapeutics, Inc · PTGX

Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗

Reporting owner

Officer — President and CEO · Director

Period of report

Sep 8, 2026

Accepted (ET)

Sep 10, 2026 · 9:17 pm EDT

Rule 10b5-1 plan

yes — trade under a plan

Issuer CIK

0001377121

Table I — non-derivative securities

Security	Date	Code	Shares	Price	A/D	Owned after	D/I
Common Stock	Sep 8, 2026	M	54,174	$21.58	A	577,142	D
Common Stock^F2	Sep 8, 2026	S	54,174	$145.87	D	522,968	D
Common Stock	Sep 9, 2026	M	63,548	$21.58	A	586,516	D
Common Stock^F3	Sep 9, 2026	S	63,548	$146.18	D	522,968	D
Common Stock	Sep 10, 2026	M	7,278	$21.58	A	530,246	D
Common Stock^F4	Sep 10, 2026	S	7,278	$144.10	D	522,968	D

Security	Conv. / exercise price	Date	Code	Shares	A/D	Exercisable	Expires	Underlying	Underlying shares	Owned after	D/I
Stock Option (right to buy)^F1	$21.58	Sep 8, 2026	M	54,174	D	—	Oct 11, 2026	Common Stock	54,174	70,826	D
Stock Option (right to buy)^F1	$21.58	Sep 9, 2026	M	63,548	D	—	Oct 11, 2026	Common Stock	63,548	7,278	D
Stock Option (right to buy)^F1	$21.58	Sep 10, 2026	M	7,278	D	—	Oct 11, 2026	Common Stock	7,278	0	D

F1The transactions set forth on this Form 4 were effected pursuant to a 10b5-1 plan adopted by the reporting person on January 30, 2026. The 10b5-1 plan provides for the exercise of fully vested stock options that expire on October 11, 2026, and the sale of shares of common stock acquired upon exercise of the stock options.
F2The price reported represents the weighted average sale price per share. The shares were sold in multiple transactions at prices ranging from $142.00 to $147.29. Upon request by the staff of the U.S. Securities and Exchange Commission (the "SEC"), 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.
F3The price reported represents the weighted average sale price per share. The shares were sold in multiple transactions at prices ranging from $144.49 to $151.27. Upon request by the staff of the SEC, 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.
F4The price reported represents the weighted average sale price per share. The shares were sold in multiple transactions at prices ranging from $142.51 to $145.19. Upon request by the staff of the SEC, 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.