Aspen Aerogels insider sale: 56,845 shares; 494,011 remain

Rhea-AI Filing Summary

Aspen Aerogels (ASPN) reported an insider transaction by its President and CEO (also a Director). On 11/13/2025, the reporting person sold 56,845 shares of common stock (Transaction Code S) under a pre‑arranged Rule 10b5‑1 trading plan. The plan was adopted on August 11, 2025 to sell a limited number of shares for tax purposes related to a one-time personal real estate transaction.

The sale price reflected a weighted average of $3.23, with trades executed between $3.15 and $3.41. Following the transaction, the reporting person beneficially owns 494,011 equity units, comprising 414,306 shares of common stock and 79,705 restricted stock units. Ownership is reported as Direct (D). The filing includes Exhibit 24.1 (Power of Attorney) and was signed by Attorney‑in‑Fact Glenn Deegan on 11/14/2025.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Young Donald R

(Last) (First) (Middle)

C/O ASPEN AEROGELS, INC.,

30 FORBES ROAD, BLDG B

(Street)

NORTHBOROUGH MA 01532

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
ASPEN AEROGELS INC [ ASPN ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	President and CEO

3. Date of Earliest Transaction (Month/Day/Year)
11/13/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	11/13/2025		S(1)		56,845	D	$3.23(2)	494,011(3)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. The transaction reported on this Form 4 was effected pursuant to a rule 10b5-1 trading plan. This plan was previously adopted by the reporting person on August 11, 2025, to sell a limited number of shares for tax purposes in connection with a one-time personal real estate transaction.

2. These transactions were executed in multiple trades at prices ranging from $3.15 to $3.41. The reporting person will provide to the staff of the Securities and Exchange Commission, the issuer, or any security holder of the issuer, upon request, full information regarding the number of shares sold at each separate price.

3. Represents 414,306 shares of Common Stock and 79,705 Restricted Stock Units.

Remarks:

Exhibit 24.1 - Power of Attorney

	/s/ Glenn Deegan, Attorney-in-Fact	11/14/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did ASPN disclose on Form 4?

The President and CEO (also a Director) sold 56,845 shares of common stock on 11/13/2025 (Transaction Code S).

Was the ASPN CEO’s sale under a Rule 10b5-1 plan?

Yes. It was effected under a Rule 10b5-1 plan adopted on August 11, 2025 for tax purposes tied to a one-time personal real estate transaction.

What was the sale price for the ASPN shares?

The weighted average price was $3.23, with trades ranging from $3.15 to $3.41.

How many ASPN shares does the CEO own after the sale?

Beneficial ownership is 494,011 equity units: 414,306 common shares and 79,705 RSUs.

What is the ownership form reported for the ASPN holdings?

The holdings are reported as Direct (D) ownership.

Who signed the ASPN Form 4 and when?

It was signed by Glenn Deegan, Attorney‑in‑Fact, on 11/14/2025. Exhibit 24.1 is a Power of Attorney.