ASPEN AEROGELS INC ASPN
COM · Common Stock · CUSIP 04523Y105 · ISIN US04523Y1055
Company in Northborough, United States
- SectorIndustrials
- IndustryWholesale-Lumber & Other Construction Materials
- HeadquartersNorthborough, MA
- Founded2001
- Websiteaerogel.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($917.5k this quarter). Holder counts are more reliable. Shares outstanding: 83.0m as of 2026-08-04, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $6.33. Options: 8 managers hold calls ($5.2m notional), 6 hold puts ($1.5m).
Trends to Q2 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 140 |
| Q4 2022 | 164 |
| Q1 2023 | 157 |
| Q2 2023 | 160 |
| Q3 2023 | 160 |
| Q4 2023 | 171 |
| Q1 2024 | 168 |
| Q2 2024 | 223 |
| Q3 2024 | 245 |
| Q4 2024 | 232 |
| Q1 2025 | 222 |
| Q2 2025 | 183 |
| Q3 2025 | 204 |
| Q4 2025 | 183 |
| Q1 2026 | 166 |
| Q2 2026 | 180 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q3 2024 | 138 | 109 |
| Q4 2024 | 149 | 112 |
| Q1 2025 | 125 | 114 |
| Q2 2025 | 99 | 119 |
| Q3 2025 | 113 | 85 |
| Q4 2025 | 80 | 123 |
| Q1 2026 | 73 | 106 |
| Q2 2026 | 99 | 67 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2025 | $11.6m | $3.3m | 0.28 |
| Q4 2025 | $6.1m | $1.1m | 0.18 |
| Q1 2026 | $2.7m | $815.3k | 0.31 |
| Q2 2026 | $5.2m | $1.5m | 0.28 |
Biggest buyers
| AMERICAN CENTURY COMPANIES INC | Added | +1.3m |
| JACOBS LEVY EQUITY MANAGEMENT, INC | Added | +839.3k |
| AQR CAPITAL MANAGEMENT LLC | Added | +750.2k |
| ACADIAN ASSET MANAGEMENT LLC | New | +684.9k |
| BlackRock, Inc. | Added | +534.1k |
| GOLDMAN SACHS GROUP INC | Added | +472.8k |
| TUDOR INVESTMENT CORP ET AL | Added | +416.3k |
| PANAGORA ASSET MANAGEMENT INC | Added | +414.5k |
| Baird Financial Group, Inc. | New | +345.2k |
| TWO SIGMA INVESTMENTS, LP | Added | +338.0k |
Biggest sellers
| NEEDHAM INVESTMENT MANAGEMENT LLC | Reduced | -1.3m |
| HRT FINANCIAL LP | Sold out | -870.4k |
| Invesco Ltd. | Reduced | -678.2k |
| Samjo Management, LLC | Sold out | -645.6k |
| CITADEL ADVISORS LLC | Reduced | -342.5k |
| GAGNON SECURITIES LLC | Reduced | -326.0k |
| Palogic Value Management, L.P. | Reduced | -264.4k |
| Point72 Asset Management, L.P. | Reduced | -247.6k |
| MILLENNIUM MANAGEMENT LLC | Reduced | -214.1k |
| JANE STREET GROUP, LLC | Sold out | -187.9k |
Biggest calls
| IMC-Chicago, LLC | Added | $1.2m196.1k shares |
| CITADEL ADVISORS LLC | Added | $1.2m182.2k shares |
| JANE STREET GROUP, LLC | Added | $1.1m169.5k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $911.1k143.7k shares |
| GROUP ONE TRADING LLC | Added | $554.8k87.5k shares |
| SIMPLEX TRADING, LLC | Added | $159.8k25.2k shares |
| Walleye Trading LLC | Reduced | $89.4k14.1k shares |
| Point72 Asset Management, L.P. | New | $39.3k6.2k shares |
Biggest puts
| CITADEL ADVISORS LLC | Reduced | $385.5k60.8k shares |
| IMC-Chicago, LLC | Reduced | $345.5k54.5k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $309.4k48.8k shares |
| JANE STREET GROUP, LLC | Added | $206.7k32.6k shares |
| GROUP ONE TRADING LLC | Reduced | $132.5k20.9k shares |
| SIMPLEX TRADING, LLC | Added | $102.1k16.1k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
| HIRSCHMAN ORIN 13G · institution new · filed 2026-10-19 | 8.6% |
| OAKTOP CAPITAL MANAGEMENT II, L.P. 13G · institution no change · filed 2025-05-15 | 5.3% |
Fell to 5% or below in the last year: Wood River Capital, LLC (0.0%, 2026-09-24), NEEDHAM INVESTMENT MANAGEMENT LLC (3.9%, 2026-08-13), VANGUARD GROUP INC (0.0%, 2026-03-26)
Insider purchases and sales since 1 Apr 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2024 | 0 | — | 0 | — | — |
| Q1 2025 | 0 | — | 0 | — | — |
| Q2 2025 | 1 | $107.0k | 0 | — | — |
| Q3 2025 | 0 | — | 1 | $47.3k | — |
| Q4 2025 | 0 | — | 1 | $183.6k | $183.6k |
| Q1 2026 | 0 | — | 0 | — | — |
| Q2 2026 | 0 | — | 0 | — | — |
| Q3 2026 | 0 | — | 0 | — | — |
| Date | Insider | Trade | Value |
|---|---|---|---|
| 2026-09-23 | Koch, Inc. +1 10% owner | Sold | $58.1m12.3m shares |
Their holding: how much the trade added to or took from the insider's holding (direct, or the trust or fund named). The same trade is sometimes reported by more than one insider, such as a fund and the director who represents it; totals count it once. A value is left blank where the reported price is far from the market price (usually a typo).
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| KIM, LLC 10.59% of their portfolio | 12.3m $77.9m | Unchanged |
| BlackRock, Inc. 0.00% of their portfolio | 5.3m $33.5m | Added +534.1k |
| OAKTOP CAPITAL MANAGEMENT II, L.P. 1.39% of their portfolio | 5.2m $32.8m | Unchanged |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 3.5m $22.4m | Added +103.1k |
| NEEDHAM INVESTMENT MANAGEMENT LLC 0.62% of their portfolio | 3.3m $20.7m | Reduced -1.3m |
| George Kaiser Family Foundation 1.93% of their portfolio | 3.2m $20.1m | Unchanged |
| STATE STREET CORP 0.00% of their portfolio | 2.6m $16.2m | Added +238.8k |
| AMERICAN CENTURY COMPANIES INC 0.01% of their portfolio | 2.5m $15.9m | Added +1.3m |
| JACOBS LEVY EQUITY MANAGEMENT, INC 0.05% of their portfolio | 2.1m $13.0m | Added +839.3k |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 1.8m $11.5m | Added +314.9k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 1.8m $11.2m | Added +229.7k |
| RICE HALL JAMES & ASSOCIATES, LLC 0.50% of their portfolio | 1.6m $10.4m | Added +82.6k |
| Invesco Ltd. 0.00% of their portfolio | 1.6m $10.3m | Reduced -678.2k |
| GAGNON SECURITIES LLC 1.88% of their portfolio | 1.5m $9.7m | Reduced -326.0k |
| DIMENSIONAL FUND ADVISORS LP 0.00% of their portfolio | 1.4m $9.2m | Added +190.9k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 1.4m $8.7m | Added +472.8k |
| ROYCE & ASSOCIATES LP 0.07% of their portfolio | 1.3m $8.4m | Added +336.7k |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 1.3m $8.1m | Added +750.2k |
| MILLENNIUM MANAGEMENT LLC 0.01% of their portfolio | 1.2m $7.5m | Reduced -214.1k |
| MARSHALL WACE, LLP 0.01% of their portfolio | 1.1m $7.3m | Reduced -116.4k |
| D. E. Shaw & Co., Inc. 0.00% of their portfolio | 1.1m $6.8m | Added +232.9k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 1.0m $6.0m | Added +38.9k |
| Telemark Asset Management, LLC 0.46% of their portfolio | 1.0m $6.3m | Unchanged |
| BNP PARIBAS FINANCIAL MARKETS 0.00% of their portfolio | 867.2k $5.5m | Added +169.3k |
| TWO SIGMA INVESTMENTS, LP 0.00% of their portfolio | 779.5k $4.9m | Added +338.0k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.00% of their portfolio | 699.0k $4.4m | Reduced -17.7k |
| ACADIAN ASSET MANAGEMENT LLC 0.01% of their portfolio | 684.9k $4.3m | New |
| FEDERATED HERMES, INC. 0.01% of their portfolio | 596.9k $3.8m | Added +146.8k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 570.7k $3.6m | Added +14.0k |
| TUDOR INVESTMENT CORP ET AL 0.01% of their portfolio | 567.4k $3.6m | Added +416.3k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 565.6k $3.6m | Added +42.1k |
| VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio | 474.4k $3.0m | Added +20.0k |
| PANAGORA ASSET MANAGEMENT INC 0.01% of their portfolio | 442.4k $2.8m | Added +414.5k |
| MORGAN STANLEY 0.00% of their portfolio | 397.1k $2.5m | Added +208.8k |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 372.1k $2.4m | Added +12.5k |
| Baird Financial Group, Inc. 0.00% of their portfolio | 345.2k $2.2m | New |
| ALGERT GLOBAL LLC 0.02% of their portfolio | 302.6k $1.9m | Reduced -23.8k |
| Trexquant Investment LP 0.01% of their portfolio | 302.4k $1.9m | New |
| RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio | 274.4k $1.7m | New |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 252.7k $1.6m | Added +11.7k |
| CITADEL ADVISORS LLC 0.00% of their portfolio | 238.7k $1.5m | Reduced -342.5k |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 229.9k $1.5m | Added +219.8k |
| XTX Topco Ltd 0.02% of their portfolio | 228.0k $1.4m | Added +26.6k |
| FIRST TRUST ADVISORS LP 0.00% of their portfolio | 222.4k $1.4m | Added +41.1k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 195.4k $1.2m | Added +9.7k |
| Palogic Value Management, L.P. 0.42% of their portfolio | 185.6k $1.2m | Reduced -264.4k |
| CITIGROUP INC 0.00% of their portfolio | 181.7k $1.2m | Reduced -52.0k |
| IRONWOOD INVESTMENT MANAGEMENT LLC 0.39% of their portfolio | 179.3k $1.1m | Added +12.7k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio | 177.4k $1.1m | Reduced -96.9k |
| ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 0.00% of their portfolio | 171.2k $1.1m | New |
| Jump Financial, LLC 0.01% of their portfolio | 168.9k $1.1m | New |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND 0.00% of their portfolio | 157.4k $997.9k | Unchanged |
| Nuveen, LLC 0.00% of their portfolio | 145.3k $921.4k | Added +10.7k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio | 130.3k $827.0k | Added +23.0k |
| PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO 0.00% of their portfolio | 128.1k $812.2k | Added +65.4k |
| Jefferies Financial Group Inc. 0.01% of their portfolio | 126.3k $800.8k | New |
| Firsthand Capital Management, Inc. 1.27% of their portfolio | 125.0k $792.5k | Unchanged |
| Russell Investments Group, Ltd. 0.00% of their portfolio | 120.3k $762.7k | Added +5.9k |
| BRIDGEWAY CAPITAL MANAGEMENT, LLC 0.01% of their portfolio | 110.0k $697.4k | Added +35.0k |
| Mitsubishi UFJ Asset Management Co., Ltd. 0.00% of their portfolio | 107.5k $681.6k | Reduced -20.0k |
| Sargent Investment Group, LLC 0.08% of their portfolio | 106.4k $674.8k | Reduced -10.0k |
| Inspire Investing, LLC 0.03% of their portfolio | 106.3k $674.1k | Reduced -44.7k |
| IEQ CAPITAL, LLC 0.00% of their portfolio | 103.3k $655.0k | New |
| RBF Capital, LLC 0.03% of their portfolio | 100.0k $634.0k | Unchanged |
| Man Group plc 0.00% of their portfolio | 90.3k $572.2k | Reduced -53.1k |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 83.3k $528.3k | Reduced -664 |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 74.1k $253.5k | Added +10.0k |
| LPL Financial LLC 0.00% of their portfolio | 69.4k $439.8k | Added +30.5k |
| FMR LLC 0.00% of their portfolio | 68.5k $434.1k | Added +64.0k |
| EntryPoint Capital, LLC 0.10% of their portfolio | 67.8k $429.8k | Reduced -78.9k |
| UBS Group AG 0.00% of their portfolio | 66.7k $422.7k | Reduced -122.6k |
| OPPENHEIMER & CO INC 0.00% of their portfolio | 64.4k $408.5k | Reduced -11.9k |
| WINTON GROUP Ltd 0.01% of their portfolio | 61.2k $388.0k | New |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 59.4k $376.4k | Added +30.8k |
| Centiva Capital, LP 0.01% of their portfolio | 56.5k $357.9k | New |
| FRANKLIN RESOURCES INC 0.00% of their portfolio | 47.9k $303.7k | Reduced -15.1k |
| Graham Capital Management, L.P. 0.01% of their portfolio | 46.3k $293.3k | Reduced -6.2k |
| Arax Advisory Partners 0.00% of their portfolio | 46.2k $292.6k | New |
| Quantbot Technologies LP 0.01% of their portfolio | 45.4k $288.0k | Added +40.9k |
| Balyasny Asset Management L.P. 0.00% of their portfolio | 43.7k $277.2k | Reduced -105.7k |
| Mariner, LLC 0.00% of their portfolio | 42.7k $270.4k | New |
| Odyssean, LLC 0.04% of their portfolio | 41.8k $264.8k | Unchanged |
| MetLife Investment Management, LLC 0.00% of their portfolio | 40.3k $255.3k | Added +25.2k |
| MERCER GLOBAL ADVISORS INC /ADV 0.00% of their portfolio | 38.7k $245.2k | New |
| State of Wyoming 0.02% of their portfolio | 38.0k $240.9k | New |
| FOX RUN MANAGEMENT, L.L.C. 0.04% of their portfolio | 37.9k $240.4k | New |
| Y-Intercept (Hong Kong) Ltd 0.00% of their portfolio | 36.8k $233.4k | New |
| Dynamic Technology Lab Private Ltd 0.05% of their portfolio | 35.1k $223.0k | Reduced -86.6k |
| SG Americas Securities, LLC 0.00% of their portfolio | 34.3k $218.0k | New |
| STATE OF WISCONSIN INVESTMENT BOARD 0.00% of their portfolio | 33.2k $210.8k | Reduced -69.4k |
| DIVERSIFIED TRUST CO 0.00% of their portfolio | 33.0k $209.5k | New |
| Concurrent Investment Advisors, LLC 0.00% of their portfolio | 32.0k $203.2k | Added +2.0k |
| Creative Planning 0.00% of their portfolio | 31.4k $199.3k | New |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.00% of their portfolio | 31.3k $198.3k | Reduced -276 |
| WEALTH ENHANCEMENT ADVISORY SERVICES, LLC 0.00% of their portfolio | 30.4k $156.8k | Added +19.4k |
| BAILARD, INC. 0.00% of their portfolio | 29.5k $187.1k | New |
| Vanguard Global Advisers, LLC 0.00% of their portfolio | 28.6k $181.2k | Unchanged |
| Cerity Partners LLC 0.00% of their portfolio | 28.4k $179.8k | Added +18.2k |
| Headlands Technologies LLC 0.02% of their portfolio | 27.4k $173.8k | New |
| nVerses Capital, LLC 0.25% of their portfolio | 25.2k $160.0k | Reduced -15.3k |