American Superconductor Corporation filed a Form 8-K on September 21, 2026, reporting that board member Barbara G. Littlefield resigned from the Board of Directors, effective September 18, 2026.

Key Highlights

  • Resignation notice: Barbara G. Littlefield informed the Board of Directors of her resignation on September 17, 2026.
  • Effective time: The resignation took effect at 12 p.m. eastern time on Friday, September 18, 2026.
  • Filing date: The current report was signed and filed on September 21, 2026.
  • Signatory: The filing was signed by John W. Kosiba, Jr., Senior Vice President and Chief Financial Officer.
  • Exchange listing: Common stock ($0.01 par value per share) trades under the symbol AMSC on the NASDAQ:AMSC Nasdaq Global Select Market.

Littlefield Departure from American Superconductor Board

According to the filing, Barbara G. Littlefield notified the Board of Directors of American Superconductor Corporation of her resignation on September 17, 2026. The resignation became effective at 12 p.m. eastern time the following day, September 18, 2026. The filing was made under Item 5.02, which covers departures of directors or certain officers, elections of directors, appointments of certain officers, and compensatory arrangements of certain officers.

The 8-K does not disclose a reason for Littlefield's departure, nor does it indicate whether the company intends to appoint a replacement director. No additional compensatory arrangements or other related disclosures were included in the filing. The report was authorized on behalf of American Superconductor Corporation and signed by John W. Kosiba, Jr., in his capacity as Senior Vice President and Chief Financial Officer, on September 21, 2026.

What Was Disclosed

American Superconductor Corporation disclosed the resignation of board member Barbara G. Littlefield, effective September 18, 2026 at 12 p.m. eastern time, following her notification to the Board on September 17, 2026. No reason or successor was named in the filing.