Note 4. Goodwill and Purchased Intangible Assets

Goodwill

Goodwill as of June 30, 2018 and 2017 and changes in the carrying amount of goodwill for the respective periods are as follows (in thousands):

	As of June 30,
	2018		2017
Balance at the beginning of the period	$	57,812	$	57,848
Currency translation		43		(36	)
Balance at the end of the period	$	57,855	$	57,812

In fiscal 2018, the Company performed its annual goodwill impairment test and determined that there was no impairment to goodwill. The Company will continue to monitor its recorded goodwill for indicators of impairment.

Purchased Intangible Assets

The Company’s intangible assets associated with purchased patent license are as follows (in thousands):

		As of June 30, 2018							As of June 30, 2017
	Useful Lives	Gross Carrying Amount		Accumulated Amortization			Net Amount		Gross Carrying Amount		Accumulated Amortization			Net Amount
	(in years)
Patent license	7	$	1,000	$	(179	)	$	821	$	1,000	$	(36	)	$	964

During fiscal 2017, the Company purchased a patent license with a useful life of seven years. The Company did not identify any triggering events that would indicate potential impairment of its definite‑lived intangible and long‑lived assets as of June 30, 2018 and 2017.

Amortization expense related to purchased intangible assets was $0.1 million, $7.7 million and $8.0 million for the years ended June 30, 2018, 2017 and 2016, respectively.

The estimated future amortization expense of purchased intangible assets as of June 30, 2018 is as follows (in thousands):

Year Ending June 30,	Amount
2019	$	143
2020		143
2021		143
2022		143
2023		143
Thereafter		106
	$	821