The Company monitors the recoverability of goodwill annually or whenever events or changes in circumstances indicate the carrying value may not be recoverable. Purchased intangible assets subject to amortization consist primarily of acquired technology and other intangible assets that include trade names, customer relationships and internally developed IP processes.

Acquired technology consists of acquired license rights for patents and know-how obtained from PD-LD, Inc., Motorola, BASF SE (BASF) and Fujifilm. These intangible assets consist of the following (in thousands):

	December 31,
	2018			2017
PD-LD, Inc.	$	1,481		$	1,481
Motorola		15,909			15,909
BASF		95,989			95,989
Fujifilm		109,462			109,462
		222,841			222,841
Less: Accumulated amortization		(111,890	)		(91,312	)
Acquired technology, net	$	110,951		$	131,529

Amortization expense related to acquired technology was $20.6 million, $20.6 million and $15.9 million for the years ended December 31, 2018, 2017 and 2016, respectively. Amortization expense is included in amortization of acquired technology and other intangible assets expense line item on the consolidated statements of income and is expected to be $20.5 million in each of the years ending December 31, 2019 through 2021, $15.8 million in the year ending December 31, 2022 and $33.6 million thereafter.

In 2000, the Company entered into a royalty-bearing license agreement with Motorola whereby Motorola granted the Company perpetual license rights to what are now 74 issued U.S. patents relating to Motorola’s OLED technologies, together with foreign counterparts in various countries. The last of the issued U.S. patents expired in 2018.

On March 9, 2011, the Company purchased these patents from Motorola, including all existing and future claims and causes of action for any infringement of the patents, pursuant to a Patent Purchase Agreement. The Patent Purchase Agreement effectively terminated the Company’s license agreement with Motorola, including any obligation to make royalty payments to Motorola. The technology acquired from Motorola was amortized over a period of 7.5 years.

On July 23, 2012, the Company entered into a Patent Sale Agreement with Fujifilm. Under the agreement, Fujifilm sold more than 1,200 OLED-related patents and patent applications in exchange for a cash payment of $105.0 million, plus costs incurred in connection with the purchase. The agreement contains customary representations and warranties and covenants, including respective covenants not to sue by both parties thereto. The agreement permitted the Company to assign all of its rights and obligations under the agreement to its affiliates, and the Company assigned, prior to the consummation of the transactions contemplated by the agreement, its rights and obligations to UDC Ireland Limited (UDC Ireland), a wholly-owned subsidiary of the Company formed under the laws of the Republic of Ireland. The transactions contemplated by the agreement were consummated on July 26, 2012. The Company recorded the $105.0 million plus $4.5 million of purchase costs as acquired technology, which is being amortized over a period of 10 years.

On June 28, 2016, UDC Ireland entered into and consummated an IP Transfer Agreement with BASF. Under the IP Transfer Agreement, BASF sold to UDC Ireland all of its rights, title and interest to certain of its owned and co-owned intellectual property rights relating to the composition of, development, manufacture and use of OLED materials, including OLED lighting and display stack technology, as well as certain tangible assets. The intellectual property includes knowhow and more than 500 issued and pending patents in the area of phosphorescent materials and technologies. These assets were acquired in exchange for a cash payment of €86.8 million ($95.8 million). In addition, UDC Ireland also took on certain rights and obligations under three joint research and development agreements to which BASF was a party. The IP Transfer Agreement also contains customary representations, warranties and covenants of the parties. UDC Ireland recorded the payment of €86.8 million ($95.8 million) and acquisition costs incurred of $217,000 as acquired technology, which is being amortized over a period of 10 years.

As a result of the Adesis acquisition in June 2016, the Company recorded $16.8 million of other intangible assets, including $10.5 million assigned to customer relationships with a weighted average life of 11.5 years, $4.8 million of internally developed IP, processes and recipes with a weighted average life of 15 years, and $1.5 million assigned to trade name and trademarks with a weighted average life of 10 years. At December 31, 2018, these other intangible assets consist of the following (in thousands):


	December 31, 2018
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Customer relationships	$	10,520	$	(2,228	)	$	8,292
Developed IP, processes and recipes		4,820		(788	)		4,032
Trade name/Trademarks		1,500		(368	)		1,132
Total identifiable intangible assets	$	16,840	$	(3,384	)	$	13,456

Amortization expense related to other intangible assets was $1.4 million, $1.4 million and $615,000 for the years ended December 31, 2018, 2017, and 2016, respectively. Amortization expense is included in amortization of acquired technology and other intangible assets expense line item on the consolidated statements of income and is expected to be $1.4 million for each of the next five fiscal years (2019 - 2023) and $6.4 million thereafter.

As a result of the Adesis acquisition, the Company recorded $15.5 million of goodwill. The Company performs its annual assessment of goodwill during the fourth quarter of the fiscal year unless events suggest an impairment may have been incurred in an interim period. Application of the goodwill impairment test requires the exercise of judgment, including the determination of the fair value of each reporting unit. The Company estimates the fair value of reporting units using an income approach based on the present value of estimated future cash flows. As part of the annual assessment of goodwill completed during the fourth quarter ended December 31, 2018, there were no significant indicators to conclude that an impairment of the goodwill associated with the acquisition of Adesis had occurred.