0000886128 2026-06-04 2026-06-04 0000886128 1 2026-06-04 2026-06-04 0000886128 2 2026-06-04 2026-06-04 0000886128 3 2026-06-04 2026-06-04 0000886128 4 2026-06-04 2026-06-04 0000886128 5 2026-06-04 2026-06-04 iso4217:USD pure S-3 S-3ASR EX-FILING FEES 0000886128 FUELCELL ENERGY INC N/A N/A S-3 FUELCELL ENERGY INC false Equity Common Stock, par value $0.0001 per share true 0.0001381 0.00 false Equity Preferred Stock, par value $0.01 per share true 0.0001381 0.00 false Debt Debt Securities true 0.0001381 0.00 false Other Warrants true 0.0001381 0.00 false Other Units true 0.0001381 0.00 0.00 0.00 0.00 0.00 0.00 An indeterminate aggregate offering price and amount of securities of each class are being registered for possible issuance from time to time at indeterminate prices and by the registrant or one or more selling security holders and as may be issuable upon conversion, redemption, exchange, exercise or settlement of any securities registered hereunder, including under any applicable anti-dilution provisions. In accordance with Rules 456(b) and 457(r) of the Securities Act of 1933, as amended, the registrant is deferring payment of all of the registration fee. See offering note 1. See offering note 1. See offering note 1. See offering note 1.