Richard I. Eisenstadt - Dec 31, 2022 Form 4 Insider Report for Altimmune, Inc. (ALT)

Role: Chief Financial Officer
Signature: /s/ Richard I. Eisenstadt
Stock symbol: ALT
Transactions as of: Dec 31, 2022
Transactions value $: -$49,811
Form type: 4
Date filed: 1/3/2023, 04:59 PM
Previous filing: Aug 3, 2022
Next filing: Feb 1, 2023

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	ALT	Common Stock, par value $0.0001	Options Exercise	$0	+12.5K	+915.08%	$0.00	13.9K	Dec 31, 2022	Direct	F1
transaction	ALT	Common Stock, par value $0.0001	Tax liability	-$49.8K	-3.03K	-21.84%	$16.45	10.8K	Dec 31, 2022	Direct	F2

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	ALT	Restricted Stock Units	Options Exercise	$0	-12.5K	-25%	$0.00	37.5K	Dec 31, 2022	Common Stock, par value $0.0001	12.5K		Direct	F1, F3

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

Explanation of Responses:

Id	Content
F1	Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of Common Stock, par value $0.0001, when vested.
F2	Vesting transaction: Shares surrendered to the Issuer solely to cover taxes associated with vesting of RSUs.
F3	The RSUs become vested and exercisable over four (4) years with 25% of the shares vesting on December 31, 2022, 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.