5. PATENT COSTS

We amortize intangible assets with definite lives on a straight-line basis over their remaining estimated useful lives, ranging from one to twelve years, and review for impairment on a quarterly basis and when events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. As of September 30, 2015, there was no indicator that an impairment existed.

We capitalized legal patent costs related to patent prosecution and maintenance. For the nine months ended September 30, 2015, we increased our capitalized patent costs by approximately $24,000 as reported to us by Auxilium through January 29, 2015 or Endo from January 29, 2015 on. These patent costs are creditable against future royalty revenues. For each period presented below, net patent costs consisted of:

	September 30, 2015			December 31, 2014
Patents	$	695,530		$	671,326
Accumulated Amortization		(410,443	)		(376,296	)
	$	285,087		$	295,030

The amortization expense for patents for the three and nine months ended September 30, 2015 was approximately $11,000 and $34,000 and $26,000 and $94,000 for the three and nine months ended September 30, 2014, respectively. The estimated aggregate amortization expense for the remaining three months of 2015 and each of the years below is approximately as follows:

2015	$	11,000
2016		37,000
2017		37,000
2018		37,000
2019		37,000
Thereafter	$	126,000