Intangible Assets

12 Months Ended

Mar. 31, 2017

5. Intangible Assets

Intangible assets consisted of the following (in thousands):


	March 31, 2017
	Weighted
	Average	Intangible
	Amortization	Assets,		Accumulated		Intangible
	Period	Gross		Amortization		Assets, Net
Manufacturing license	17 years	$	3,700	$	3,684	$	16
Technology	10 years		2,240		1,605		635
Trade name & parts, service and TA100 customer relationships	1.2 to 5 years		1,766		1,766		—
Total		$	7,706	$	7,055	$	651


	March 31, 2016
	Weighted
	Average	Intangible
	Amortization	Assets,		Accumulated		Intangible
	Period	Gross		Amortization		Assets, Net
Manufacturing license	17 years	$	3,700	$	3,635	$	65
Technology	10 years		2,240		1,381		859
Backlog	Various		490		473		17
Trade name & parts, service and TA100 customer relationships	1.2 to 5 years		1,766		1,766		—
Total		$	8,196	$	7,255	$	941

Amortization expense for the intangible assets was $0.3 million and $0.4 million for each of the fiscal years ended March 31, 2017 and 2016. During the years ended March 31, 2017 and 2016, approximately $17,000 and $0.1 million of purchased TA100 backlog was written off to align with management’s decision to limit the production of TA100 systems on a case-by-case basis for key customers.

Expected future amortization expense of intangible assets as of March 31, 2017 is as follows (in thousands):


	Amortization
Year Ending March 31,	Expense
2018		240
2019		224
2020		187
Thereafter		—
Total expected future amortization	$	651

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 $32,100 and $35,000 were earned by Solar for the fiscal years ended March 31, 2017 and 2016, respectively. Earned royalties of approximately $10,000 and $35,000 were unpaid as of March 31, 2017 and 2016, respectively, and are included in accrued expenses in the accompanying balance sheets.