Grant Douglas Thoele - 01 Oct 2025 Form 4/A - Amendment Insider Report for ASPEN AEROGELS INC (ASPN)

Role: CFO & Treasurer
Signature: /s/ Glenn Deegan, Attorney-in-Fact
Issuer symbol: ASPN
Transactions as of: 01 Oct 2025
Net transactions value: $0
Form type: 4/A - Amendment
Filing time: 19 Dec 2025, 17:15:04 UTC
Date Of Original Report: 03 Oct 2025
Next filing: 06 Mar 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Thoele Grant Douglas	CFO & Treasurer	30 FORBES ROAD, BUILDING B, NORTHBOROUGH	/s/ Glenn Deegan, Attorney-in-Fact	19 Dec 2025	0002089743

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	ASPN	Common Stock	Award	$0	+10,273	+68%	$0.000000	25,392	01 Oct 2025	Direct	F1, F2, 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 the right to receive one share of Common Stock upon vesting. The RSUs vest as to one-third of the shares on March 5, 2026, an additional one-third of the shares on March 5, 2027 and the remaining one-third of the shares on March 5, 2028.
F2	This Form 4/A is being filed to correct the reported total of Securities Beneficially Owned following the reported transaction. The beneficially owned shares previously reported did not include 10,511 restricted stock units granted prior to the October 1, 2025, transaction date.
F3	Represents 4,608 shares of Common Stock and 20,784 RSUs.