Aspen Aerogels ASPN Institutional Ownership

Ownership Summary

Aspen Aerogels Inc (NYSE:ASPN) has 163 institutional investors that have filed 13F reports for the period ending March 2026.

• Their combined ownership stood at 83.9% of outstanding shares in March 2026, down from 87.8% in December 2025.
• They increased total shares held in Aspen Aerogels by 8.13% from the prior quarter, while the number of investors in ASPN decreased 25.91% year over year.
• Among the 163 funds, 78 bought more Aspen Aerogels shares, 57 sold down, and 28 held their ground.
• In total, institutional investors held 69.39Mn shares in Aspen Aerogels as of March 2026, up by 5.22Mn shares quarter on quarter, and down 6.68Mn shares year over year.
• As of March 31, 2026, the biggest holder of Aspen Aerogels is KIM, LLC at 12.28Mn shares, representing 14.84% of shares outstanding.
• The biggest buyers of Aspen Aerogels for the quarter ending March 2026 included VANGUARD CAPITAL MANAGEMENT LLC (3.44Mn), JACOBS LEVY EQUITY MANAGEMENT, INC (1.08Mn), ROYCE & ASSOCIATES LP (986.51K), HRT FINANCIAL LP (870.44K), D. E. Shaw & Co., Inc. (810.36K).
• The largest sales of ASPN for the quarter ending March 2026 came from Invesco Ltd. (1.83Mn), Goldman Sachs Group Inc (1.69Mn), Samjo Management, LLC (951.42K), DIMENSIONAL FUND ADVISORS LP (747.48K), Jpmorgan Chase & Co (518.25K).
• Business Quant data shows the 10 biggest positions in Aspen Aerogels as of March 2026 are held by KIM, LLC (12.28Mn), OAKTOP CAPITAL MANAGEMENT II, L.P. (5.17Mn), BlackRock, Inc. (4.74Mn), NEEDHAM INVESTMENT MANAGEMENT LLC (4.52Mn), VANGUARD CAPITAL MANAGEMENT LLC (3.44Mn), GEORGE KAISER FAMILY FOUNDATION (3.17Mn), State Street Corp (2.32Mn), Invesco Ltd. (2.3Mn), GAGNON SECURITIES LLC (1.86Mn), RICE HALL JAMES & ASSOCIATES, LLC (1.55Mn).