5. Patents and Licenses

9 Months Ended

Sep. 30, 2016

Patents And Licenses

Patents and Licenses

Purchased patents and licenses paid for the use of other entities’ patents are amortized over the useful life of the patent or license. The following tables provide information regarding patents and licenses (dollars in thousands):

September 30, 2016						December 31, 2015
Weighted Average Original Life (years)		Gross Carrying Amount		Accumulated Amortization		Weighted Average Original Life (years)		Gross Carrying Amount		Accumulated Amortization
	15.67	$	13,840	$	11,835		15.67	$	13,840	$	11,647

Aggregate amortization expense for patents and licenses was $63,000 for the three months ended both September 30, 2016 and 2015, and $188,000 and $282,000 for the nine months ended September 30, 2016 and 2015, respectively.

Estimated future amortization expense for each of the years set forth below ending December 31 is as follows (in thousands):

2017	$155
2018	$123
2019	$123
2020	$119
2021	$119