Steven R. Mitchell - 13 May 2026 Form 4 Insider Report for ASPEN AEROGELS INC (ASPN)

Reporting relationship: Director
Issuer ticker: ASPN
Reported as of: 13 May 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 14 May 2026, 17:30:11 UTC
Prior SEC filing: 07 Apr 2026
Next SEC filing: 21 May 2026
Source filing: View source filing
Reporting owner signature: /s/ Glenn Deegan, Attorney-in-Fact

Key filing fact

Steven R. Mitchell filed Form 4 for ASPEN AEROGELS INC (ASPN) on 14 May 2026.

Key facts

This page summarizes Steven R. Mitchell's Form 4 filing for ASPEN AEROGELS INC (ASPN).
2 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 14 May 2026, 17:30.

Change

Previous filing in this sequence was filed on 07 Apr 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001610279 Primary reporting owner

Mitchell Steven R

Relationship: Director
Address: C/O ASPEN AEROGELS, INC.,, 30 FORBES ROAD, BLDG B, NORTHBOROUGH
Signature: /s/ Glenn Deegan, Attorney-in-Fact
Signature date: 14 May 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

ASPN transaction

Common Stock

Award

Transaction value
Shares: +10,370
Change %: +7.1%
Price: $0.000000^*
Shares after: 156,898
Date: 13 May 2026
Ownership: Direct
Footnotes: F1, F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

ASPN transaction Derivative

Stock Options (Right to Buy)

Award

Transaction value
Shares: +8,706
Change %
Price: $0.000000^*
Shares after: 8,706
Date: 13 May 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 8,706
Exercise price: $5.40
Footnotes: F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

The reporting person was granted Restricted Stock Units ("RSUs") representing a portion of the annual grant of equity for service as a non-employee director pursuant to the Issuer's Non-Employee Director Compensation Policy. Each RSU represents the right to receive one share of Common Stock upon vesting. These RSUs will vest on the earlier of (a) May 13, 2027, or (b) the day prior to the Issuer's annual meeting of stockholders to be held in 2027.

Footnote F2

Represents 146,528 shares of Common Stock and 10,370 RSUs.

Footnote F3

The reporting person was granted options representing the remaining portion of the annual grant of equity for service as a non-employee director pursuant to the Issuer's Non-Employee Director Compensation Policy. The options will vest on the earlier of (a) May 13, 2027, or (b) the day prior to the Issuer's annual meeting of stockholders to be held in 2027.

SEC remarks

Exhibit 24.1 - Power of Attorney