9. INTANGIBLE ASSETS

Amortization expense related to intangible assets is as follows (in thousands):


	Three Months Ended				Six Months Ended
	April 1, 2016		April 3, 2015		April 1, 2016		April 3, 2015
Cost of revenue	$	6,642	$	7,347	$	13,809	$	12,706
Selling, general and administrative		6,304		3,096		10,727		4,149

Total	$	12,946	$	10,443	$	24,536	$	16,855

Intangible assets consist of the following (in thousands):


	April 1, 2016			October 2, 2015
Acquired technology	$	164,365		$	162,536
Customer relationships		202,646			144,070
In-process research and development		8,000			8,000
Trade name		3,400			3,400

Total		378,411			318,006
Less accumulated amortization		(98,876	)		(74,340	)

Intangible assets — net	$	279,535		$	243,666

A summary of the activity in intangible assets and goodwill follows (in thousands):


	Total			Acquired Technology			Customer Relationships		In-Process Research and Development		Trade Name		Goodwill
Balance at October 2, 2015	$	411,352		$	162,536		$	144,070	$	8,000	$	3,400	$	93,346
Acquired		88,796			10,400			55,350		—		—		23,046
Currency translation adjustment		5,505			836			3,226		—		—		1,443
Other intangibles purchased		681			681			—		—		—		—
Impairments of intangible assets		(10,088	)		(10,088	)		—		—		—		—

Balance at April 1, 2016	$	496,246		$	164,365		$	202,646	$	8,000	$	3,400	$	117,835

As of April 1, 2016, our estimated amortization of our intangible assets in future fiscal years, subject to the completion of the purchase price allocation for the FiBest and Metelics acquisitions, was as follows (in thousands):


	2016 Remaining		2017		2018		2019		2020		Thereafter		Total
Amortization expense	$	25,124		50,312		46,911		40,383		32,604		72,802	$	268,136

Our trade name is an indefinite-lived intangible assets. During development, in-process research and development (IPR&D) is not subject to amortization and is tested for impairment annually or more frequently if events or changes in circumstances indicate that the asset might be impaired. The impairment test consists of a comparison of the fair value to its carrying amount. If the carrying value exceeds its fair value, an impairment loss is recognized in an amount equal to that excess. Once an IPR&D project is complete, it becomes a definite long-lived intangible asset and is evaluated for impairment in accordance with our policy for long-lived assets.

Accumulated amortization for acquired technology and customer relationships was $64.5 million and $34.4 million, respectively, as of April 1, 2016, and $39.4 million and $12.8 million, respectively, as of April 3, 2015.

During the second quarter of fiscal year 2016, we made a strategic decision to exit the product line and end programs associated with our GaN-on Silicon Carbide license and technology transfer to focus on development of our GaN-on-Silicon efforts. As a result of this strategic decision, we determined that the intangible assets and contractual commitments under the long term technology licensing and transfer agreement signed in July 2013, as well as certain dedicated fixed assets and inventory, would no longer have any future benefit. The associated charges incurred during the second quarter of fiscal 2016 was $13.0 million which included a write-off of $10.1 million of intangible assets, $0.6 million of fixed assets, $0.3 million of contractual commitments and $2.0 million of inventory.