ESSEX INVESTMENT MANAGEMENT CO LLC
Position in AMSC — American Superconductor Corp /De/
CIK 201772
BOSTON, MA
Position in AMSC
as of Jun 30, 2026
· filed Aug 6, 2026
Position Value
$9,212,438
+$1,509,600 QoQ
Shares Held
221,933
-2.5% QoQ
Ownership
0.458%
of shares outstanding
% of Portfolio
1.24%
of 13F equity value
Holder Rank
#36
of 276 holders
Holding Since
Mar 2020
16 quarters on record
Voting authority
Sole 74%
Shared 0%
None 26%
Common Shares in AMSC Over Time
Shares Held
Position Value (USD)
Position in Specialty Industrial Machinery
Industrials · as of Jun 30, 2026ESSEX INVESTMENT MANAGEMENT CO LLC holds $37,740,140 across 13 Specialty Industrial Machinery names. AMSC ranks #3 (24.4% of the industry book) .
| # | Ticker | Company | Shares | Value (USD) | Open |
|---|---|---|---|---|---|
| 1 | GHM |
Graham Corp
|
93,405 | $11,562,604 | |
| 2 | GEV |
GE Vernova Inc.
|
8,283 | $9,731,365 | |
| 3 | AMSC |
American Superconductor Corp /De/
This page
|
221,933 | $9,212,438 | |
| 4 | MIR |
Mirion Technologies, Inc.
|
295,060 | $5,290,425 | |
| 5 | XYL |
Xylem Inc.
|
10,462 | $1,236,713 | |
| 6 | BWEN |
Broadwind, Inc.
|
94,671 | $457,260 | |
| 7 | GTES |
Gates Industrial Corp Ltd.
|
1,996 | $55,828 | |
| 8 | OPTT |
Ocean Power Technologies, Inc.
|
204,864 | $53,264 |
All Filings in AMSC
Export CSV
16 filing rows on record
| Report Date | Value (USD) | Shares | Type | Discretion | Filed | |
|---|---|---|---|---|---|---|
| 2026-06-30 | $9,212,438 | 221,933 | Shares | Sole | 2026-08-06 | |
| 2026-03-31 | $7,702,838 | 227,558 | Shares | Sole | 2026-05-11 | |
| 2025-12-31 | $6,192,132 | 215,154 | Shares | Sole | 2026-02-13 | |
| 2025-09-30 | $14,585,055 | 245,581 | Shares | Sole | 2025-11-06 | |
| 2025-06-30 | $12,696,280 | 346,042 | Shares | Sole | 2025-08-12 | |
| 2025-03-31 | $6,752,088 | 372,221 | Shares | Sole | 2025-05-07 | |
| 2024-12-31 | $10,587,845 | 429,876 | Shares | Sole | 2025-02-07 | |
| 2024-09-30 | $10,962,341 | 464,506 | Shares | Sole | 2024-10-10 | |
| 2024-06-30 | $13,510,672 | 577,626 | Shares | Sole | 2024-08-12 | |
| 2024-03-31 | $7,888,813 | 583,924 | Shares | Sole | 2024-05-03 | |
| 2023-12-31 | $6,951,560 | 624,018 | Shares | Sole | 2024-02-08 | |
| 2023-09-30 | $5,291,289 | 700,833 | Shares | Sole | 2023-11-09 | |
| 2020-12-31 | $3,793,899 | 161,994 | Shares | Sole | 2021-02-12 | |
| 2020-09-30 | $2,622,429 | 181,107 | Shares | Sole | 2020-11-12 | |
| 2020-06-30 | $1,425,847 | 175,381 | Shares | Sole | 2020-08-04 | |
| 2020-03-31 | $1,317,002 | 240,329 | Shares | Sole | 2020-05-04 | |
| No filing history on record for this holder in this stock. | ||||||