James R. Gruber - 12 Jan 2026 Form 4 Insider Report for Eton Pharmaceuticals, Inc. (ETON)

Role: Chief Financial Officer
Signature: /s/ James R. Gruber
Issuer symbol: ETON
Transactions as of: 12 Jan 2026
Net transactions value: -$35,473
Form type: 4
Filing time: 14 Jan 2026, 18:02:48 UTC
Previous filing: 12 Dec 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Gruber James R.	Chief Financial Officer	C/O ETON PHARMACEUTICALS, INC., 21925 W. FIELD PARKWAY, SUITE 235, DEERPARK	/s/ James R. Gruber	14 Jan 2026	0001923165

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	ETON	Common Stock	Tax liability	$35,473	-2,293	-1.1%	$15.47	213,420	14 Jan 2026	Direct	F1, F2, F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	ETON	Employee Stock Option (Right to Buy)	Award	$0	+40,655	+19%	$0.000000	254,075	12 Jan 2026	Common Stock	40,655	$15.47	Direct	F4
transaction	ETON	Restricted Stock Units	Award	$0	+25,856	+10%	$0.000000	279,931	12 Jan 2026	Common Stock	25,856		Direct	F5, F6

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
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 $15.46 to $15.48. 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.