7.  Intangible Assets

 

The Company recorded amortization expense of $0.1 million for each of the three and six months ended September 30, 2016. The Company recorded amortization expense of $0.1 million for each of the three and six months ended September 30, 2015. Intangible assets consisted of the following as of September 30, 2016 and March 31, 2016 (in thousands):

 

 

 

 

Expected future amortization expense of intangible assets as of September 30, 2016 is as follows (in thousands):

 

 

The manufacturing license provides the Company with the ability to manufacture recuperator cores previously purchased from Solar Turbines Incorporated (“Solar”). The Company is required to pay a per-unit royalty fee over a seventeen-year period for cores manufactured and sold by the Company using the technology. Royalties of approximately $6,400 and $7,000 were earned by Solar for the three months ended September 30, 2016 and 2015, respectively. Royalties of approximately $14,700 and $19,200 were earned by Solar for the six months ended September 30, 2016 and 2015, respectively. Earned royalties of approximately $6,400 and $35,000 were unpaid as of September 30, 2016 and March 31, 2016, respectively, and are included in accounts payable and accrued expenses in the accompanying balance sheets.