Public ownership evidence

American Superconductor Corp (AMSC) Ownership Disclosures

Read AMSC insider transactions, institutional 13F filings and Congressional disclosures with report dates, public availability and original receipts.

As of 2026-09-21T21:23:19.000Z

Recent Form 4 activity

2026-09-212026-09-18Littlefield Barbara G.A1,607Not reported

90-day public availability window, up to 50 records.

Recent institutional filing receipts

These are raw ticker-matched positions in recent 13F receipts, including amendments. They are not deduplicated current ownership totals. Open the manager profile to inspect its effective filing book.

Corient Private Wealth LP2026-06-302026-08-285,372$222,993None
VIRGINIA RETIREMENT SYSTEMS ET Al2026-03-312026-08-2618,800$636,380None
CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM2026-06-302026-08-2550,888$2,112,361None
CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM2026-06-302026-08-252,112,361$50,888,000None
Assenagon Asset Management S.A.2026-06-302026-08-226,224$258,358None
Bullock Wealth Management Group2026-06-302026-08-20190$7,585None
Kingsview Wealth Management, LLC2026-06-302026-08-206,995$290,362None
Archer Investment Corp2026-06-302026-08-20100$4,151None
MERCER GLOBAL ADVISORS INC /ADV2026-06-302026-08-205,550$230,381None
Ensign Peak Advisors, Inc2026-03-312026-08-194,550$154,018None
Ensign Peak Advisors, Inc2025-12-312026-08-194,550$130,949None
Ensign Peak Advisors, Inc2025-09-302026-08-198,850$525,602None
DARK FOREST CAPITAL MANAGEMENT LP2026-06-302026-08-1511,422$474,127None
STANCE CAPITAL LLC2026-06-302026-08-15220$9,132None
SEI INVESTMENTS CO2026-06-302026-08-1582,479$3,423,703None
SEI INVESTMENTS CO2026-06-302026-08-152,736$113,520None
Federation des caisses Desjardins du Quebec2026-06-302026-08-152,495$103,567None
JPL Wealth Management, LLC2026-06-302026-08-152$84None
Marex Group Ltd2026-06-302026-08-156,900$286,419None
Basecamp Wealth Advisors LLC2026-06-302026-08-1527$1,121None
Polymer Capital Management (US) LLC2026-06-302026-08-1534,521$1,432,967None
Quarry LP2026-06-302026-08-1595$3,943None
ROI Financial Advisors, LLC2026-06-302026-08-1512,842$533,071None
T. Rowe Price Investment Management, Inc.2026-06-302026-08-15306,182$12,710,000None
XTX Topco Ltd2026-06-302026-08-1530,848$1,280,500None
Aquatic Capital Management LLC2026-06-302026-08-1532,081$1,331,682None
CHARLES SCHWAB INVESTMENT MANAGEMENT INC2026-06-302026-08-15399,125$16,567,679None
Sixth Street Partners Management Company, L.P.2026-06-302026-08-15399,125$16,567,679None
ExodusPoint Capital Management, LP2026-06-302026-08-158,325$345,571None
Defiance ETFs, LLC2026-06-302026-08-1599,395$3,967,848None
Qube Research & Technologies Ltd2026-06-302026-08-15250,573$10,401,285None
Caption Management, LLC2026-06-302026-08-1524,500$1,016,995Call
OSAIC HOLDINGS, INC.2026-06-302026-08-15968$40,182None
OSAIC HOLDINGS, INC.2026-06-302026-08-1511,683$484,954None
MetLife Investment Management, LLC2026-06-302026-08-1527,526$1,142,604None
JANE STREET GROUP, LLC2026-06-302026-08-1539,933$1,657,619None
JANE STREET GROUP, LLC2026-06-302026-08-15130,386$5,412,323None
JANE STREET GROUP, LLC2026-06-302026-08-15373,500$15,503,985Put
JANE STREET GROUP, LLC2026-06-302026-08-15420,400$17,450,804Call
Orion Porfolio Solutions, LLC2026-06-302026-08-156,318$262,260None
BOOTHBAY FUND MANAGEMENT, LLC2026-06-302026-08-157,414$307,755None
AWM Investment Company, Inc.2026-06-302026-08-15951,604$39,501,082None
Legal & General Group Plc2026-06-302026-08-15743,002$30,842,012None
Legal & General Group Plc2026-06-302026-08-159,289$385,586None
Legal & General Group Plc2026-06-302026-08-154,572$189,784None
HRT FINANCIAL LP2026-06-302026-08-15298,420$12,387,000None
Ensign Peak Advisors, Inc2026-06-302026-08-153,050$126,606None
SUSQUEHANNA INTERNATIONAL GROUP, LLP2026-06-302026-08-15204,900$8,505,399Call
SUSQUEHANNA INTERNATIONAL GROUP, LLP2026-06-302026-08-15188,600$7,828,786Put
SUSQUEHANNA INTERNATIONAL GROUP, LLP2026-06-302026-08-15235,235$9,764,605None

90-day public filing window, up to 50 source positions.

Recent Congressional disclosures

No records are available for this view.

Bounded public source preview, up to 25 disclosed events.

How to read the disclosure dates

The tables report different things: insider transactions, institutional positions and Congressional transaction ranges. Read each table with its source dates and units. They cannot be added into a combined ownership percentage.

  1. Company insiders

    SEC Form 4 purchases, sales and awards report transactions and their public filing availability.

  2. Institutional managers

    13F reports disclose delayed quarter-end positions. They are not a record of trades between quarters.

  3. Congressional filers

    Periodic transaction reports disclose transaction dates and amount brackets. Public filing dates determine what researchers could know.

Read the transaction codes

Awards use transaction code A, purchases P and sales S. An acquisition from an award is not the same as an open-market purchase. Joint filers may share a transaction. Use original receipts and availability dates to interpret the events.