11. Supplemental Financial Statement Information

Other Assets

As of December 31, 2023, the Company had $2.4 million of royalty-related assets remaining, recorded within the Prepaid and other current assets and Other assets line items 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 product. The effective royalty rate is calculated as the prepaid royalty settlement divided by total projected C200 System units over the 15-year amortization period. On a quarterly basis, the Company performs a re-forecast of C200 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 December 31, 2023.

The current and long-term portions of prepaid royalties, included in prepaid and other current assets and other assets, respectively, consisted of (in thousands):

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Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consisted of (in thousands):

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