15. Other Assets

The Company was a party to a Development and License Agreement with Carrier Corporation (“Carrier”) regarding the payment of royalties on the sale of each of the Company’s 200 kilowatt (“C200”) microturbines. In 2013, the Company reached its repayment threshold level and the fixed rate royalty was reduced by 50%. On July 25, 2018, the Company and Carrier entered into a Second Amendment to the Development and License Agreement (“Second Amendment”) whereby the Company agreed to pay Carrier approximately $3.0 million to conclude the Company’s current

royalty obligation under the Development and License Agreement, dated as of September 4, 2007, as amended (“Development Agreement”) and release the Company from any future royalty payment obligations. The Second Amendment also removed non-compete provisions from the Development Agreement, allowing the Company to design market or sell its C200 System in conjunction with any energy system and compete with Carrier products in the CCHP market.

On September 19, 2018, the Company paid in full the negotiated royalty settlement of $3.0 million to Carrier, and as such, there is no further royalty obligation to Carrier. The prepaid royalty of $3.0 million has been recorded under the captions “Prepaid expenses and other current assets” and “Other assets” in the accompanying consolidated balance sheets and will be amortized in the accompanying consolidated statements of operations over a 15-year amortization 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 will perform a re-forecast of C200 System unit shipments, to determine if an adjustment to the effective royalty rate is necessary. Accordingly, if the Company’s future projections change, its effective royalty rates would change, which could affect the amount and timing of royalty expense the Company recognizes. If impairment exists, then the prepaid royalty asset could be written down to fair value. Prepaid royalties are classified as current assets to the extent that such amounts will be recognized in the Company’s consolidated statements of operations within the next twelve months. The current and long-term portions of prepaid royalties, included in other current assets and other assets, respectively, consisted of (in thousands):

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