16. Balance Sheet Information

Prepaid Expenses and Other Assets

As of September 30, 2025, the Company had $2.1 million of royalty-related assets remaining recorded within the “Prepaid expenses and other current assets” line item on the accompanying Condensed Consolidated Balance Sheets. The assets are being amortized over a 15-year period through September 2033 using an effective royalty rate.

A 15-year amortization period is the minimum expected life cycle of the current generation of products. The effective royalty rate is calculated as the prepaid royalty settlement divided by total projected microturbine system units over the 15-year amortization period. On a quarterly basis, the Company performs a re-forecast of microturbine system unit shipments to determine if an adjustment to the effective royalty rate is necessary and accordingly whether an impairment exists. The Company determined an impairment did not exist as of September 30, 2025, or March 31, 2025.

The current and long-term portions of prepaid royalties and prepaid and other assets were as follows (in thousands):

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