Annual report [Section 13 and 15(d), not S-K Item 405]

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
Mar. 31, 2026
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies Purchase Commitments As of March 31, 2026 the Company had firm commitments to purchase inventories of approximately $49.3 million through Fiscal 2029. Certain inventory delivery dates and related payments are not scheduled; therefore, amounts under these firm purchase commitments will be payable upon the receipt of the related inventory. Lease Commitments Refer to Note 10 – Leases. Related Party Transactions On December 7, 2023 (the "Effective Date"), in connection with the Company's emergence from Chapter 11 bankruptcy, certain assets of the predecessor entity ("Reorganized PrivateCo”) including the Company's trademarks and distributor support services business were retained by Reorganized PrivateCo and held by Capstone Distributor Support Services Corporation ("CDSS"), an entity controlled by Goldman Sachs. A series of agreements were entered into on the Effective Date governing the relationship between the Company and CDSS, as described below. On March 31, 2026, in connection with the closing of the March 2026 PIPE (see Note 15) the Company completed a series of transactions that substantially unwound these related party arrangements, as further described below. Reorganized PrivateCo Services Agreement On the Effective Date, the Operating Subsidiary entered into a Services Agreement with Reorganized PrivateCo (the "Reorganized PrivateCo Services Agreement"), pursuant to which Reorganized PrivateCo provided the Operating Subsidiary's distributors, on a subcontracted basis, with certain ongoing and transition services related to Reorganized PrivateCo's distributor support services business. In consideration for these services, Reorganized PrivateCo paid the Operating Subsidiary a service fee equal to 90% of Reorganized PrivateCo's income (as defined in the Reorganized PrivateCo Services Agreement), less itemized expenses incurred and paid in direct support of the Operating Subsidiary's distributors. The Company recognized $2.3 million and $2.5 million in other income for DSS service fees for Fiscal 2026 and Fiscal 2025, respectively. In connection with the closing of the March 2026 PIPE, the Operating Subsidiary and the Company entered into an Asset Purchase Agreement with CDSS pursuant to which the Operating Subsidiary acquired the Distributor Support Services assets previously held by CDSS for a purchase price of $1.0 million (the "DSS Asset Acquisition"). As a result of the DSS Asset Acquisition, the Reorganized PrivateCo Services Agreement was terminated, and the distributor support services business is now fully owned and operated by the Operating Subsidiary. Accordingly, the Reorganized PrivateCo Services Agreement is no longer in effect as of March 31, 2026. Trademark License Agreement On the Effective Date, the Company entered into a Trademark License Agreement (the "Trademark License Agreement") with Reorganized PrivateCo, as licensor, pursuant to which Reorganized PrivateCo granted the Company a non-exclusive, royalty-bearing, non-transferable, non-sublicensable (except to affiliates), worldwide, perpetual and irrevocable (each subject to the terms of the Trademark License Agreement) license to use the Capstone trademarks solely in connection with the Company's business. In consideration for this license, the Company paid Reorganized PrivateCo an annual royalty of $100,000. The Trademark License Agreement included a provision that if Reorganized PrivateCo did not use any of the Capstone trademarks for six consecutive months, those trademarks would be assigned to the Company for no further consideration. Additionally, Reorganized PrivateCo was restricted from assigning the Capstone trademarks to any third party without the Company's prior consent, not to be unreasonably withheld. In connection with the DSS Asset Acquisition and the related unwinding of the Reorganized PrivateCo structure, the Trademark License Agreement was superseded, and the Trademarks were acquired by the Company. See Note 8 – Intangible Assets for additional information. Services Agreement between the Company and the Operating Subsidiary On the Effective Date, the Company entered into a Services Agreement with the Operating Subsidiary (the "New Capstone Services Agreement"), pursuant to which the Company provided certain services to the Operating Subsidiary in its capacity as majority equity holder, and in consideration, the Operating Subsidiary would reimburse the Company for its reasonable audit, board, and executive compensation expenses incurred in connection with being a publicly traded company (the "New Capstone Services Fee"). The New Capstone Services Fee was subject to an annual cap of $2,500,000 per fiscal year, increased on April 1 of each year by the greater of 3.5% or the Consumer Price Index as published by the U.S. Bureau of Labor Statistics as of March 31 of the prior year; provided that the increase effective April 1, 2024 was equal to 1.75%. Following the closing of the March 2026 PIPE and the full redemption of the Preferred Units, Capstone Green Energy LLC became a wholly owned subsidiary of the Company. Preferred Unit Redemption On March 31, 2026, the Company redeemed all outstanding Preferred Units for $83.5 million. See Note 13 for additional information regarding the redemption and Note 15 for information on funding. Legal Proceedings Capstone Turbine Corporation v. Turbine International, LLC. On February 3, 2020, Capstone Turbine Corporation filed suit against its former distributor, Turbine International, LLC (“Turbine Intl.”), in the Superior Court of California alleging breach of contract relating to the parties’ prior distributor relationship (which terminated at the end of March 2018) and Turbine Intl.’s failure to satisfy its payment obligations under certain financial agreements, namely an accounts receivable agreement and promissory note in favor of Capstone. The Company subsequently modified its complaint to include Turbine Intl. guarantors as defendants. The Company was seeking approximately $4.8 million in compensatory damages, along with injunctive relief and attorney’s fees, interest, and costs. In 2024, the Court ordered default judgments first against Turbine International and then against the other defendants. The default judgement in the amount of approximately $7.3 million, which included pre-judgement interest and costs of the suite, was entered and placed on the docket in June 2025. The Company has prevailed in this proceeding. The ability of Capstone to collect on the judgement is unclear, as the defendants are overseas or without U.S.-based assets, therefor we have not recorded a receivable as of March 31, 2026.

Commitments and Contingencies

12 Months Ended

Mar. 31, 2026

Commitments and Contingencies Disclosure [Abstract]

12. Commitments and Contingencies

Purchase Commitments

As of March 31, 2026 the Company had firm commitments to purchase inventories of approximately $49.3 million through Fiscal 2029. Certain inventory delivery dates and related payments are not scheduled; therefore, amounts under these firm purchase commitments will be payable upon the receipt of the related inventory.

Lease Commitments

Refer to Note 10 – Leases.

Related Party Transactions

On December 7, 2023 (the "Effective Date"), in connection with the Company's emergence from Chapter 11 bankruptcy, certain assets of the predecessor entity ("Reorganized PrivateCo”) including the Company's trademarks and distributor support services business were retained by Reorganized PrivateCo and held by Capstone Distributor Support Services Corporation ("CDSS"), an entity controlled by Goldman Sachs. A series of agreements were entered into on the Effective Date governing the relationship between the Company and CDSS, as described below. On March 31, 2026, in connection with the closing of the March 2026 PIPE (see Note 15) the Company completed a series of transactions that substantially unwound these related party arrangements, as further described below.

Reorganized PrivateCo Services Agreement

On the Effective Date, the Operating Subsidiary entered into a Services Agreement with Reorganized PrivateCo (the "Reorganized PrivateCo Services Agreement"), pursuant to which Reorganized PrivateCo provided the Operating Subsidiary's distributors, on a subcontracted basis, with certain ongoing and transition services related to Reorganized PrivateCo's distributor support services business. In consideration for these services, Reorganized PrivateCo paid the Operating Subsidiary a service fee equal to 90% of Reorganized PrivateCo's income (as defined in the Reorganized PrivateCo Services Agreement), less itemized expenses incurred and paid in direct support of the Operating Subsidiary's distributors.

The Company recognized $2.3 million and $2.5 million in other income for DSS service fees for Fiscal 2026 and Fiscal 2025, respectively.

In connection with the closing of the March 2026 PIPE, the Operating Subsidiary and the Company entered into an Asset Purchase Agreement with CDSS pursuant to which the Operating Subsidiary acquired the Distributor Support Services assets previously held by CDSS for a purchase price of $1.0 million (the "DSS Asset Acquisition"). As a result of the DSS Asset Acquisition, the Reorganized PrivateCo Services Agreement was terminated, and the distributor support services business is now fully owned and operated by the Operating Subsidiary. Accordingly, the Reorganized PrivateCo Services Agreement is no longer in effect as of March 31, 2026.

Trademark License Agreement

On the Effective Date, the Company entered into a Trademark License Agreement (the "Trademark License Agreement") with Reorganized PrivateCo, as licensor, pursuant to which Reorganized PrivateCo granted the Company a non-exclusive, royalty-bearing, non-transferable, non-sublicensable (except to affiliates), worldwide, perpetual and irrevocable (each subject to the terms of the Trademark License Agreement) license to use the Capstone trademarks solely in connection with the Company's business. In consideration for this license, the Company paid Reorganized PrivateCo an annual royalty of $100,000.

The Trademark License Agreement included a provision that if Reorganized PrivateCo did not use any of the Capstone trademarks for six consecutive months, those trademarks would be assigned to the Company for no further consideration. Additionally, Reorganized PrivateCo was restricted from assigning the Capstone trademarks to any third party without the Company's prior consent, not to be unreasonably withheld.

In connection with the DSS Asset Acquisition and the related unwinding of the Reorganized PrivateCo structure, the Trademark License Agreement was superseded, and the Trademarks were acquired by the Company. See Note 8 – Intangible Assets for additional information.

Services Agreement between the Company and the Operating Subsidiary

On the Effective Date, the Company entered into a Services Agreement with the Operating Subsidiary (the "New Capstone Services Agreement"), pursuant to which the Company provided certain services to the Operating Subsidiary in its capacity as majority equity holder, and in consideration, the Operating Subsidiary would reimburse the Company for its reasonable audit, board, and executive compensation expenses incurred in connection with being a publicly traded company (the "New Capstone Services Fee").

The New Capstone Services Fee was subject to an annual cap of $2,500,000 per fiscal year, increased on April 1 of each year by the greater of 3.5% or the Consumer Price Index as published by the U.S. Bureau of Labor Statistics as of March 31 of the prior year; provided that the increase effective April 1, 2024 was equal to 1.75%.

Following the closing of the March 2026 PIPE and the full redemption of the Preferred Units, Capstone Green Energy LLC became a wholly owned subsidiary of the Company.

Preferred Unit Redemption

On March 31, 2026, the Company redeemed all outstanding Preferred Units for $83.5 million. See Note 13 for additional information regarding the redemption and Note 15 for information on funding.

Legal Proceedings

Capstone Turbine Corporation v. Turbine International, LLC.

On February 3, 2020, Capstone Turbine Corporation filed suit against its former distributor, Turbine International, LLC (“Turbine Intl.”), in the Superior Court of California alleging breach of contract relating to the parties’ prior distributor relationship (which terminated at the end of March 2018) and Turbine Intl.’s failure to satisfy its payment obligations under certain financial agreements, namely an accounts receivable agreement and promissory note in favor of Capstone. The Company subsequently modified its complaint to include Turbine Intl. guarantors as defendants. The Company was seeking approximately $4.8 million in compensatory damages, along with injunctive relief and attorney’s fees, interest, and costs. In 2024, the Court ordered default judgments first against Turbine International and then against the other defendants. The default judgement in the amount of approximately $7.3 million, which included pre-judgement interest and costs of the suite, was entered and placed on the docket in June 2025. The Company has prevailed in this proceeding. The ability of Capstone to collect on the judgement is unclear, as the defendants are overseas or without U.S.-based assets, therefor we have not recorded a receivable as of March 31, 2026.