미국 초전도체 공사
MX ˙ BMV ˙ US0301112076
SecurityMX:AMSC / American Superconductor Corporation
InstitutionVanguard Group Inc
Latest Disclosed Ownership0 shares
Ownership 0.00%
Vanguard Group Inc ownership in AMSC / American Superconductor Corporation

2026-03-26 - Vanguard Group Inc has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 0 shares of American Superconductor Corporation (MX:AMSC). This represents 0.0 percent ownership of the company. In their previous filing dated 2026-01-30 , Vanguard Group Inc had reported owning 3,526,632 shares, indicating a decrease of -100.00 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File
Date
Effective
Date
Form Prev
Shares
Latest
Shares
ΔShares
(Percent)
Ownership
(Percent)
ΔOwnership
(Percent)
2026-03-26 2026-03-26 13G/A 3,526,632 0 -100.00 0.00 -100.00
2026-01-30 2026-01-30 13G/A 2,426,278 3,526,632 45.35 7.40 16.90
2024-11-12 2024-11-12 13G/A 2,426,278 2,426,278 0.00 6.33 0.00
2024-11-04 2024-11-04 13G 2,426,278 6.33

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

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)
2026-01-29 2025-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 3,526,632 576,831 19.55 101,496 -42.06 0.0015
2025-11-07 2025-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 2,949,801 502,754 20.55 175,189 95.13 0.0026
2025-08-11 2025-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 2,447,047 159,462 6.97 89,782 116.36 0.0015
2025-05-09 2025-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 2,287,585 64,650 2.91 41,497 -24.21 0.0008
2025-02-11 2024-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 2,222,935 -203,343 -8.38 54,751 -4.38 0.0010
2024-11-13 2024-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 2,426,278 339,558 16.27 57,260 17.32 0.0010
2024-08-13 2024-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 2,086,720 387,786 22.83 48,808 112.65 0.0009
2024-05-10 2024-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,698,934 396,814 30.47 22,953 58.24 0.0005
2024-03-11 2023-12-31 13F/A-1 AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,302,120 14,855 1.15 14,506 49.26 0.0003
2024-02-14 2023-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,302,120 14,855 14,506 0.0003
2023-12-18 2023-09-30 13F/A-1 AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,287,265 43,439 3.49 9,719 24.81 0.0002
2023-11-14 2023-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,287,265 43,439 9,719 0.0000
2023-08-14 2023-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,243,826 280 0.02 7,786 27.53 0.0002
2023-07-14 2023-03-31 13F/A-1 AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,243,546 149,382 13.65 6,106 51.64 0.0002
2023-05-15 2023-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,243,546 149,382 6,106 0.0000
2023-02-10 2022-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,094,164 3,269 0.30 4,027 -15.74 0.0001
2022-11-14 2022-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,090,895 -30,175 -2.69 4,778 -17.72 0.0001
2022-08-12 2022-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,121,070 -108,381 -8.82 5,807 -37.93 0.0002
2022-05-13 2022-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,229,451 18,425 1.52 9,356 -28.99 0.0002
2022-02-14 2021-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,211,026 10,491 0.87 13,176 -24.73 0.0003
2021-11-12 2021-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,200,535 8,261 0.69 17,504 -15.58 0.0004
2021-08-13 2021-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,192,274 1,288 0.11 20,734 -8.18 0.0005
2021-05-14 2021-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,190,986 42,384 3.69 22,581 -16.06 0.0006
2021-02-12 2020-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,148,602 161,770 16.39 26,900 88.26 0.0008
2020-11-16 2020-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 986,832 -72,412 -6.84 14,289 65.92 0.0005
2020-08-14 2020-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 1,059,244 62,947 6.32 8,612 57.73 0.0003
2020-05-15 2020-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 996,297 3,178 0.32 5,460 -29.96 0.0002
2020-02-14 2019-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 993,119 64,540 6.95 7,796 7.09 0.0003
2019-11-14 2019-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 928,579 65,956 7.65 7,280 -9.06 0.0003
2019-08-14 2019-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 862,623 110,545 14.70 8,005 -17.23 0.0003
2019-05-15 2019-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 752,078 29,020 4.01 9,671 19.96 0.0004
2019-02-14 2018-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 723,058 -31,540 -4.18 8,062 53.74 0.0004
2018-12-13 2018-09-30 13F/A-2 AMERICAN SUPERCONDUCTOR SHS NEW 030111207 754,598 15,850 2.15 5,244 1.39 0.0002
2018-11-23 2018-09-30 13F/A-1 AMERICAN SUPERCONDUCTOR SHS NEW 030111207 754,598 0 5,244 0.0002
2018-11-14 2018-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 754,598 15,850 5,244
2018-08-14 2018-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 738,748 20,372 2.84 5,172 23.70 0.0002
2018-05-15 2018-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 718,376 160,389 28.74 4,181 106.37 0.0002
2018-02-14 2017-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 557,987 39,828 7.69 2,026 -13.86 0.0001
2017-11-14 2017-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 518,159 130,577 33.69 2,352 31.32 0.0001
2017-08-24 2017-06-30 13F/A-1 AMERICAN SUPERCONDUCTOR SHS NEW 030111207 387,582 -73,710 -15.98 1,791 -43.41 0.0001
2017-08-11 2017-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 387,582 -73,710 1,791
2017-05-12 2017-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 461,292 -12,335 -2.60 3,165 -9.31 0.0002
2017-02-14 2016-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 473,627 23,291 5.17 3,490 10.58 0.0002
2016-11-14 2016-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 450,336 -10,803 -2.34 3,156 -18.91 0.0002
2016-08-10 2016-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 461,139 41,509 9.89 3,892 22.04 0.0002
2016-05-13 2016-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 419,630 36,160 9.43 3,189 30.59 0.0002
2016-02-08 2015-12-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 383,470 9,544 2.55 2,442 50.83 0.0002
2015-11-12 2015-09-30 13F/A-1 AMERICAN SUPERCONDUCTOR SHS NEW 030111207 373,926 12,882 3.57 1,619 -14.25 0.0001
2015-11-12 2015-09-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 5,005,458 184,025
2015-08-13 2015-06-30 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 361,044 133,614 58.75 1,888 28.87 0.0001
2015-05-15 2015-03-31 13F/A-1 AMERICAN SUPERCONDUCTOR SHS NEW 030111207 227,430 -1,899,191 -89.31 1,465 -6.98 0.0001
2015-05-14 2015-03-31 13F AMERICAN SUPERCONDUCTOR SHS NEW 030111207 227,430 1,465
2015-02-12 2014-12-31 13F AMERICAN SUPERCONDUCTOR COM 030111108 2,126,621 140,276 7.06 1,575 -43.77 0.0001
2014-11-12 2014-09-30 13F AMERICAN SUPERCONDUCTOR COM 030111108 1,986,345 248,293 14.29 2,801 -1.13 0.0002
2014-08-11 2014-06-30 13F AMERICAN SUPERCONDUCTOR COM 030111108 1,738,052 29,100 1.70 2,833 2.98 0.0002
2014-05-13 2014-03-31 13F AMERICAN SUPERCONDUCTOR COM 030111108 1,708,952 245,818 16.80 2,751 14.67 0.0002
2014-02-12 2013-12-31 13F AMERICAN SUPERCONDUCTOR COM 030111108 1,463,134 -40,460 -2.69 2,399 -31.81 0.0002
2013-11-07 2013-09-30 13F AMERICAN SUPERCONDUCTOR COM 030111108 1,503,594 73,781 5.16 3,518 -6.78 0.0003
2013-08-13 2013-06-30 13F AMERICAN SUPERCONDUCTOR COM 030111108 1,429,813 1,429,813 3,774 0.0004
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.