8. Intangible Assets

Intangible assets consist principally of acquired patents and technology, customer lists and relationships, licenses and trademarks. The Company recorded amortization expense of $0.7 million and $0.6 million for the three months ended June 30, 2018 and 2017, respectively. The Company recorded amortization expense of $2.0 million and $1.9 million for the nine months ended June 30, 2018 and 2017, respectively.

Intangible assets consisted of the following:

	June 30, 2018
(Dollars in thousands)	Weighted Average Original Life (Years)		Gross Carrying Amount		Accumulated Amortization			Net
Definite-lived intangible assets:
Customer lists and relationships		8.9	$	18,168	$	(9,004	)	$	9,164
Developed technology		11.5		9,675		(2,139	)		7,536
Non-compete		5.0		230		(138	)		92
Patents and other		16.5		2,322		(1,533	)		789
Subtotal				30,395		(12,814	)		17,581
Unamortized intangible assets:
In-process research and development				269		—			269
Trademarks and trade names				580		—			580
Total			$	31,244	$	(12,814	)	$	18,430

	September 30, 2017
(Dollars in thousands)	Weighted Average Original Life (Years)		Gross Carrying Amount		Accumulated Amortization			Net
Definite-lived intangible assets:
Customer lists and relationships		8.9	$	18,293	$	(7,834	)	$	10,459
Developed technology		11.7		9,297		(1,478	)		7,819
Non-compete		5.0		230		(103	)		127
Patents and other		16.5		2,321		(1,423	)		898
Subtotal				30,141		(10,838	)		19,303
Unamortized intangible assets:
In-process research and development				679		—			679
Trademarks and trade names				580		—			580
Total			$	31,400	$	(10,838	)	$	20,562

Based on the intangible assets in service as of June 30, 2018, excluding any possible future amortization associated with acquired in-process research and development (“IPR&D”), which has not met technological feasibility as of June 30, 2018, estimated amortization expense for the remainder of fiscal 2018 and each of the next five fiscal years is as follows (in thousands):

Remainder of 2018	$	675
2019		2,701
2020		2,526
2021		2,387
2022		2,347
2023		1,745

Future amortization amounts presented above are estimates. Actual future amortization expense may be different as a result of future acquisitions, impairments, completion or abandonment of IPR&D intangible assets, changes in amortization periods, foreign currency translation rates, or other factors.

The Company defines IPR&D as the value of technology acquired for which the related projects have substance and are incomplete. IPR&D acquired in a business acquisition is recognized at fair value and requires the IPR&D to be capitalized as an indefinite-lived intangible asset until completion of the IPR&D project or abandonment. Upon completion of the development project (generally when regulatory approval to market the product is obtained), an impairment assessment is performed prior to amortizing the asset over its estimated useful life. If the IPR&D projects are abandoned, the related IPR&D assets would be written off. During the first nine months of fiscal 2018, we reclassified $0.4 million of acquired IPR&D to developed technology as the technology was commercialized.