BRYNJELSEN SEAN 4

4 · Eton Pharmaceuticals, Inc. · Filed Jan 14, 2026

Form 4

Period: 2026-01-12

DirectorPresident & CEO10% Owner

Transactions

Tax Payment
Common Stock
[F1][F2][F3]
2026-01-01$15.39/sh−5,015$77,181→ 2,889,266 total
Award
Employee Stock Option (Right to Buy)
[F4]
2026-01-12+158,046→ 3,047,312 total
Exercise: $15.47Exp: 2036-01-11→ Common Stock (158,046 underlying)
Award
Restricted Stock Units
[F5][F6]
2026-01-12+100,517→ 3,147,829 total
→ Common Stock (100,517 underlying)

Footnotes (6)

[F1]Shares withheld by the Issuer to satisfy applicable withholding taxes upon the vesting of restricted stock units.
[F2]The shares were sold in multiple trades at prices ranging from $15.39 to $15.42. The price reported above reflects the weighted average sales price.
[F3]The Reporting Person will provide upon request by the Securities and Exchange Commission staff, the issuer, or a security holder of the issuer, full information regarding the number of shares purchased or sold at each separate price.
[F4]The shares subject to the option shall vest in 48 equal monthly installments from the date of grant until fully vested and exercisable on January 12, 2030.
[F5]Each restricted stock unit represents a contingent right to receive one share of ETON Common Stock.
[F6]The restricted stock units vest in four equal annual installments beginning January 12, 2027, contingent upon the reporting person being employed by the issuer on the date(s) of vesting.

Signature

/s/ James R. Gruber|2026-01-14

Documents

1 file