Altimmune, Inc. — Director's Dealing 2026

Feb 27, 2026

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Altimmune, Inc. (ALT)
CIK: 0001326190
Period of Report: 2026-02-26

Reporting Person: Roberts M Scot (N/A)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2026-02-26	Stock Options (option to buy)	$4.46	A	222670	Acquired	2036-02-26	Common Stock, par value $0.0001 (222670)	Direct
2026-02-26	Restricted Stock Units	$	A	95430	Acquired		Common Stock, par value $0.0001 (95430)	Direct

Footnotes

F1: The shares underlying the option become vested and exercisable over four (4) years with 25% of the shares vesting on February 26, 2027, with the remainder vesting in equal monthly installments for the following thirty-six (36) months, subject to the reporting person's continued service on each applicable vesting date.

F2: Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of Common Stock, par value $0.0001, when vested.

F3: The RSUs become vested over four (4) years with 25% of the shares vesting February 26, 2027, with the remainder vesting in equal annual installments for the following three (3) years, subject to the reporting person's continued service through the applicable vesting date, and have no expiration date.