Goodwill represents the excess of the purchase price over the fair value of the net tangible and identifiable intangible assets acquired in a business combination. The carrying value of goodwill as of January 30, 2021 and February 1, 2020 is $5.3 billion. See “Note 4 - Business Combinations” for discussion of the acquisitions and changes to the carrying value of goodwill.

The Company has identified that its business operates as a single operating segment with two components that it has concluded can be aggregated into a single reporting unit. The Company’s annual test for goodwill impairment as of the last day of the fourth quarter of fiscal 2021 did not result in any impairment charge.

In connection with the Cavium acquisition on July 6, 2018, the Aquantia acquisition on September 19, 2019 and the Avera acquisition on November 5, 2019, the Company recognized $3.3 billion of intangible assets. As of January 30, 2021 and February 1, 2020, net carrying amounts are as follows (in thousands, except for weighted-average remaining amortization period):


	January 30, 2021
	Gross Carrying Amounts		Accumulated Amortization and Write-Offs		Net Carrying Amounts		Weighted -Average Remaining Amortization Period (Years)
Developed technologies	$	2,454,000	$	(724,215)	$	1,729,785	5.54
Customer contracts and related relationships	643,000		(228,845)		414,155		5.62
Trade names	23,000		(14,240)		8,760		2.20
Total acquired amortizable intangible assets	3,120,000		(967,300)		2,152,700		5.54
IPR&D	118,000		—		118,000		n/a
Total acquired intangible assets	$	3,238,000	$	(967,300)	$	2,270,700

The Company regularly analyzes the results of its business to determine whether events or circumstances exist that indicate whether the carrying amount of the intangible assets may not be recoverable. During the second quarter of fiscal 2021, impairment charges of $50.3 million related to certain intangible assets acquired from Cavium were recognized as part of restructuring actions. The gross carrying amounts and the accumulated amortization of those impaired intangible assets were excluded from the table above. See “Note 6 - Restructuring” for additional information.


	February 1, 2020
	Gross Carrying Amounts		Accumulated Amortization and Write-Offs		Net Carrying Amounts		Weighted-Average Remaining Amortization Period (Years)
Developed technologies	$	2,511,000	$	(413,735)	$	2,097,265	6.41
Customer contracts and related relationships	643,000		(128,939)		514,061		6.61
Trade names	23,000		(8,726)		14,274		2.96
Total acquired amortizable intangible assets	3,177,000		(551,400)		2,625,600		6.43
IPR&D	139,000		—		139,000		n/a
Total acquired intangible assets	$	3,316,000	$	(551,400)	$	2,764,600

The intangible assets are amortized on a straight-line basis over the estimated useful lives, except for certain Cavium customer contracts and related relationships, which are amortized using an accelerated method of amortization over the expected customer lives in order to more closely align with the pattern of realization of economic benefits expected to be obtained. The IPR&D will be accounted for as an indefinite-lived intangible asset and will not be amortized until the underlying projects reach technological feasibility and commercial production at which point the IPR&D will be amortized over the estimated useful life. Useful lives for these IPR&D projects are expected to range between 3 to 10 years. In the event the IPR&D is abandoned, the related assets will be written off.

Amortization for acquired intangible assets was $443.6 million, $368.1 million and $183.3 million during the years ended January 30, 2021, February 1, 2020 and February 2, 2019 respectively.