Form 8-K

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02. Results of Operations and Financial Condition.

On August 7, 2025, Aspen Aerogels, Inc. announced its financial results for the second quarter of 2025, which ended June 30, 2025, and also discussed business developments. A copy of the press release containing such announcement is attached hereto as Exhibit 99.1.

The information set forth in the press release, except for the information set forth under the headings “Second Half of 2025 Financial Outlook,” “Aspen Announces CFO Transition to Internal Successor” and “About Aspen Aerogels, Inc.,” together with the forward-looking statement disclaimer at the end of the press release, is incorporated by reference into this Item 2.02 of this Current Report on Form 8-K.

Item 7.01. Regulation FD Disclosure.

The information set forth under the headings “Second Half of 2025 Financial Outlook,” “Aspen Announces CFO Transition to Internal Successor” and “About Aspen Aerogels, Inc.,” together with the forward-looking statement disclaimer at the end of the press release, is incorporated by reference into this Item 7.01 of this Current Report on Form 8-K.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

Exhibit Number		Description

99.1		Press Release issued by Aspen Aerogels, Inc. on August 7, 2025
104		Cover Page Interactive Data File (embedded within the Inline XBRL document)

The press release may contain hypertext links to information on our website. The information on our website is not incorporated by reference into this Current Report on Form 8-K and does not constitute a part of this Form 8-K.

The information contained in this Current Report on Form 8-K and Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section, nor shall it be deemed incorporated by reference into any registration statement or other filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Delaware	001-36481	04-3559972
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(I.R.S. Employer Identification No.)

30 Forbes Road, Building B Northborough, Massachusetts	01532
(Address of Principal Executive Offices)	(Zip Code)

Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock	ASPN	The New York Stock Exchange

	ASPEN AEROGELS, INC.


Date: August 7, 2025	By:	/s/ Ricardo C. Rodriguez
	Name:	Ricardo C. Rodriguez
	Title:	Chief Financial Officer and Treasurer

☐	Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐	Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐	Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))