As filed with the Securities and Exchange Commission on March 3, 2017

Registration No. 333 -

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

ASPEN AEROGELS, INC.

(Exact name of registrant as specified in its charter)

30 Forbes Road, Building B

Northborough, Massachusetts 01532

(508) 691-1111

(Address, including zip code, of principal executive offices)

ASPEN AEROGELS, INC. 2014 EMPLOYEE, DIRECTOR AND CONSULTANT EQUITY INCENTIVE PLAN

(Full Title of the Plan)

Donald R. Young

President and Chief Executive Officer

Aspen Aerogels, Inc.

30 Forbes Road, Building B

Northborough, Massachusetts 01532

(508) 691-1111

(Name, address and telephone number, including area code, of agent for service)

Copies to:

Sahir Surmeli, Esq.

John T. Rudy, Esq.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

One Financial Center

Boston, Massachusetts 02111

(617) 542-6000

Facsimile: (617) 542-2241

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

CALCULATION OF REGISTRATION FEE

EXPLANATORY NOTE

This Registration Statement registers an aggregate of 467,396 additional shares of the Registrant’s common stock reserved under the Aspen Aerogels, Inc. 2014 Employee, Director and Consultant Equity Incentive Plan (the “2014 Plan”), representing an increase of 467,396 shares reserved under the 2014 Plan effective January 1, 2017 by operation of the 2014 Plan’s “evergreen” provision. This Registration Statement registers additional securities of the same class as other securities for which a registration statement filed on Form S-8 of the Registrant relating to an employee benefit plan is effective (SEC File No. 333-198124). The information contained in the Registrant’s registration statement on Form S-8 (SEC File No. 333-198124) is hereby incorporated by reference pursuant to General Instruction E of Form S-8.

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PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 8. Exhibits.

The Index to Exhibits immediately preceding the exhibits is incorporated herein by reference.

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SIGNATURES

The Registrant. Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in Northborough, Massachusetts on March 3, 2017.

Each person whose signature appears below constitutes and appoints Donald R. Young, John F. Fairbanks and
Poongunran Muthukumaran, and each of them singly, his true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution in each of them singly, for him and in his name, place and stead, and in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement on Form S-8 of Aspen Aerogels, Inc., and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting to the attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite or necessary to be done in or about the premises, as full to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that the attorneys-in-fact and agents or any of each of them or their substitute may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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Aspen Aerogels, Inc.

INDEX TO EXHIBITS FILED WITH

FORM S-8 REGISTRATION STATEMENT 

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