Aspen Aerogels, Inc.
US ˙ NYSE ˙ US04523Y1055

SecurityASPN / Aspen Aerogels, Inc.
InstitutionDimensional Fund Advisors Lp
Latest Disclosed Ownership1,256,480 shares
Latest Disclosed Value $ 4,296,033
Dimensional Fund Advisors Lp reports 37.30% decrease in ownership of ASPN / Aspen Aerogels, Inc.

On May 7, 2026 - Dimensional Fund Advisors Lp filed a 13F-HR form disclosing ownership of 1,256,480 shares of Aspen Aerogels, Inc. (US:ASPN) valued at $4,297,162 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 2,003,963 shares of Aspen Aerogels, Inc.. This represents a change in shares of -37.30% during the quarter. The current value of the position is $7,086,547 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-07 2026-03-31 13F ASPEN AEROGELS COM 04523Y105 1,256,480 -747,483 -37.30 4,296 -24.25 0.0002
2026-02-12 2025-12-31 13F ASPEN AEROGELS COM 04523Y105 2,003,963 -248,050 -11.01 5,672 -63.82 0.0012
2025-11-12 2025-09-30 13F ASPEN AEROGELS COM 04523Y105 2,252,013 -197,090 -8.05 15,675 8.11 0.0034
2025-08-12 2025-06-30 13F ASPEN AEROGELS COM 04523Y105 2,449,103 -58,481 -2.33 14,499 -9.52 0.0034
2025-05-13 2025-03-31 13F ASPEN AEROGELS COM 04523Y105 2,507,584 488,953 24.22 16,024 -33.18 0.0040
2025-02-13 2024-12-31 13F ASPEN AEROGELS COM 04523Y105 2,018,631 409,862 25.48 23,983 -46.17 0.0058
2024-11-07 2024-09-30 13F ASPEN AEROGELS COM 04523Y105 1,608,769 234,138 17.03 44,550 35.87 0.0108
2024-08-09 2024-06-30 13F ASPEN AEROGELS COM 04523Y105 1,374,631 240,921 21.25 32,790 64.33 0.0086
2024-05-10 2024-03-31 13F ASPEN AEROGELS COM 04523Y105 1,133,710 317,941 38.97 19,953 55.00 0.0054
2024-02-07 2023-12-31 13F ASPEN AEROGELS COM 04523Y105 815,769 576,006 240.24 12,874 524.60 0.0038
2023-11-09 2023-09-30 13F ASPEN AEROGELS COM 04523Y105 239,763 226,401 1,694.36 2,062 1,862.86 0.0007
2023-08-09 2023-06-30 13F ASPEN AEROGELS COM 04523Y105 13,362 -117,443 -89.78 105 -89.22 0.0000
2023-05-12 2023-03-31 13F ASPEN AEROGELS COM 04523Y105 130,805 -491 -0.37 974 97,300.00 0.0003
2023-02-09 2022-12-31 13F ASPEN AEROGELS COM 04523Y105 131,296 -7,664 -5.52 2 -99.92 0.0005
2022-11-10 2022-09-30 13F ASPEN AEROGELS COM 04523Y105 138,960 -191,697 -57.97 1,282 -60.74 0.0005
2022-08-12 2022-06-30 13F ASPEN AEROGELS COM 04523Y105 330,657 -110,590 -25.06 3,265 -78.54 0.0012
2022-05-13 2022-03-31 13F ASPEN AEROGELS COM 04523Y105 441,247 21,112 5.03 15,214 -27.27 0.0047
2022-02-09 2021-12-31 13F ASPEN AEROGELS COM 04523Y105 420,135 12,351 3.03 20,918 11.50 0.0063
2021-11-12 2021-09-30 13F ASPEN AEROGELS COM 04523Y105 407,784 16,561 4.23 18,761 60.39 0.0060
2021-08-12 2021-06-30 13F ASPEN AEROGELS COM 04523Y105 391,223 -15,935 -3.91 11,697 41.27 0.0037
2021-05-14 2021-03-31 13F ASPEN AEROGELS COM 04523Y105 407,158 61,608 17.83 8,280 43.58 0.0027
2021-03-08 2020-12-31 13F/A-2 ASPEN AEROGELS COM 04523Y105 345,550 13,834 4.17 5,767 58.78 0.0021
2021-02-11 2020-12-31 13F ASPEN AEROGELS COM 04523Y105 345,550 13,834 5,767 2,082.7339
2020-11-12 2020-09-30 13F ASPEN AEROGELS COM 04523Y105 331,716 10,743 3.35 3,632 71.97 0.0015
2020-08-13 2020-06-30 13F ASPEN AEROGELS COM 04523Y105 320,973 178 0.06 2,112 7.21 0.0009
2020-05-14 2020-03-31 13F ASPEN AEROGELS COM 04523Y105 320,795 1,302 0.41 1,970 -20.53 0.0010
2020-02-14 2019-12-31 13F ASPEN AEROGELS COM 04523Y105 319,493 629 0.20 2,479 31.30 0.0009
2019-11-12 2019-09-30 13F ASPEN AEROGELS COM 04523Y105 318,864 0 0.00 1,888 -16.97 0.0007
2019-08-13 2019-06-30 13F ASPEN AEROGELS COM 04523Y105 318,864 9,057 2.92 2,274 187.85 0.0009
2019-08-12 2019-03-31 13F/A-2 ASPEN AEROGELS COM 04523Y105 309,807 -1,429 -0.46 790 19.16 0.0003
2019-05-10 2019-03-31 13F ASPEN AEROGELS COM 04523Y105 309,807 -1,429 790
2019-02-26 2018-12-31 13F/A-1 ASPEN AEROGELS COM 04523Y105 311,236 2,700 0.88 663 -52.98 0.0003
2019-02-13 2018-12-31 13F ASPEN AEROGELS COM 04523Y105 311,236 2,700 663
2018-11-13 2018-09-30 13F ASPEN AEROGELS COM 04523Y105 308,536 109,241 54.81 1,410 44.32 0.0005
2018-08-10 2018-06-30 13F ASPEN AEROGELS COM 04523Y105 199,295 38,780 24.16 977 42.63 0.0004
2018-05-11 2018-03-31 13F ASPEN AEROGELS COM 04523Y105 160,515 30,593 23.55 685 8.04 0.0003
2018-02-12 2017-12-31 13F ASPEN AEROGELS COM 04523Y105 129,922 49,773 62.10 634 81.66 0.0003
2017-11-13 2017-09-30 13F ASPEN AEROGELS COM 04523Y105 80,149 63,605 384.46 349 371.62 0.0002
2017-08-11 2017-06-30 13F ASPEN AEROGELS COM 04523Y105 16,544 16,544 74 0.0000
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.