Needham discloses 5.3% Aspen Aerogels (ASPN) stake in Schedule 13G

Rhea-AI Filing Summary

Needham Investment Management L.L.C., Needham Asset Management, LLC, and George A. Needham report a passive 5.3% ownership stake in Aspen Aerogels Inc. They collectively report beneficial ownership of 4,351,700 shares of Aspen Aerogels common stock, with shared voting and dispositive power over all reported shares and no sole authority.

All of the securities are directly owned by advisory clients of Needham Investment Management L.L.C., and no individual client is described as holding more than 5% of the common stock. The filing states the shares were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of Aspen Aerogels.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

Aspen Aerogels Inc

(Name of Issuer)

Common Stock, par value $0.00001 per share

(Title of Class of Securities)

04523Y105

(CUSIP Number)

12/31/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 04523Y105

1

Names of Reporting Persons

NEEDHAM INVESTMENT MANAGEMENT L.L.C.

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 4,351,700.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 4,351,700.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

4,351,700.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.3 %

12

Type of Reporting Person (See Instructions)

IA, OO

SCHEDULE 13G

CUSIP No. 04523Y105

1

Names of Reporting Persons

NEEDHAM ASSET MANAGEMENT, LLC

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 4,351,700.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 4,351,700.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

4,351,700.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.3 %

12

Type of Reporting Person (See Instructions)

HC, OO

SCHEDULE 13G

CUSIP No. 04523Y105

1

Names of Reporting Persons

GEORGE A. NEEDHAM

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 0.00
6	Shared Voting Power 4,351,700.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 4,351,700.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

4,351,700.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.3 %

12

Type of Reporting Person (See Instructions)

HC, IN

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Aspen Aerogels Inc
(b)	Address of issuer's principal executive offices: 30 Forbes Road, Building B, Northborough, Massachusetts 01532
Item 2.
(a)	Name of person filing: Needham Investment Management L.L.C. Needham Asset Management, LLC George A. Needham
(b)	Address or principal business office or, if none, residence: Needham Investment Management L.L.C. 250 Park Avenue, 10th Floor New York, New York 10117-1099 United States of America Needham Asset Management, LLC c/o Needham Investment Management L.L.C. 250 Park Avenue, 10th Floor New York, New York 10117-1099 United States of America George A. Needham c/o Needham Investment Management L.L.C. 250 Park Avenue, 10th Floor New York, New York 10117-1099 United States of America
(c)	Citizenship: Needham Investment Management L.L.C. - Delaware Needham Asset Management, LLC - Delaware George A. Needham - United States
(d)	Title of class of securities: Common Stock, par value $0.00001 per share
(e)	CUSIP No.: 04523Y105
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: Needham Investment Management L.L.C. - 4,351,700 Needham Asset Management, LLC - 4,351,700 George A. Needham - 4,351,700
(b)	Percent of class: Needham Investment Management L.L.C. - 5.3% Needham Asset Management, LLC - 5.3% George A. Needham - 5.3%
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: Needham Investment Management L.L.C. - 0 Needham Asset Management, LLC - 0 George A. Needham - 0
	(ii) Shared power to vote or to direct the vote: Needham Investment Management L.L.C. - 4,351,700 Needham Asset Management, LLC - 4,351,700 George A. Needham - 4,351,700
	(iii) Sole power to dispose or to direct the disposition of: Needham Investment Management L.L.C. - 0 Needham Asset Management, LLC - 0 George A. Needham - 0
	(iv) Shared power to dispose or to direct the disposition of: Needham Investment Management L.L.C. - 4,351,700 Needham Asset Management, LLC - 4,351,700 George A. Needham - 4,351,700
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. All of the securities reported in this Schedule 13G are directly owned by advisory clients of Needham Investment Management L.L.C. None of those advisory clients may be deemed to beneficially own more than 5% of the Common Stock, par value $0.00001 per share
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary. Please see Exhibit B attached hereto.
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

NEEDHAM INVESTMENT MANAGEMENT L.L.C.

Signature:	By: /s/ James W. Giangrasso
Name/Title:	James W. Giangrasso, Chief Financial Officer
Date:	02/13/2026

NEEDHAM ASSET MANAGEMENT, LLC

Signature:	By: /s/ James W. Giangrasso
Name/Title:	James W. Giangrasso, Authorized Person
Date:	02/13/2026

GEORGE A. NEEDHAM

Signature:	By: /s/ George A. Needham
Name/Title:	George A. Needham
Date:	02/13/2026

Comments accompanying signature: * Each Reporting Person disclaims beneficial ownership of the reported securities except to the extent of his, her or its pecuniary interest therein, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose. To the extent that "ownership of 5 percent or less of a class" was indicated in Item 5, such response only applies to the Reporting Person(s) that indicated elsewhere herein that it beneficially owns five percent (5%) or less of the class.

Exhibit Information

Exhibit A - Joint Filing Agreement Exhibit B - Control Person Identification

FAQ

What ownership stake in Aspen Aerogels (ASPN) does Needham report?

Needham-affiliated entities report beneficial ownership of 4,351,700 Aspen Aerogels common shares, representing 5.3% of the class. This stake is reported with shared voting and dispositive power and reflects holdings managed across advisory client accounts.

Who are the reporting persons in this Aspen Aerogels (ASPN) Schedule 13G?

The Schedule 13G lists Needham Investment Management L.L.C., Needham Asset Management, LLC, and George A. Needham as reporting persons. Each reports beneficial ownership of 4,351,700 Aspen Aerogels common shares, or 5.3% of the outstanding class.

Do Needham entities have control intent over Aspen Aerogels (ASPN)?

The filing certifies the securities were acquired and are held in the ordinary course of business and not for changing or influencing control of Aspen Aerogels. It also states they are not held in connection with any transaction having that control-related purpose.

Who directly owns the Aspen Aerogels (ASPN) shares reported by Needham?

The Schedule 13G explains that all reported securities are directly owned by advisory clients of Needham Investment Management L.L.C. The reporting persons indicate that none of these advisory clients may be deemed to beneficially own more than 5% of Aspen Aerogels’ common stock.

What kind of voting and dispositive power does Needham report over Aspen Aerogels (ASPN) shares?

Each reporting person reports 0 shares with sole voting or dispositive power and 4,351,700 shares with shared voting and shared dispositive power. This reflects coordinated authority over these Aspen Aerogels common shares rather than exclusive individual control.

When did the ownership level triggering this Aspen Aerogels (ASPN) filing occur?

The Schedule 13G lists December 31, 2025 as the date of event requiring the statement. That date marks when the reporting persons’ beneficial ownership position met the threshold that necessitated this beneficial ownership disclosure.