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. In connection with the completion of the Wi-Fi business divestiture on December 6, 2019, the Company allocated goodwill of $511.1 million on a relative fair value basis to the divested business. See “Note 1 - Basis of Presentation” for further discussion of the divestiture. In connection with the Aquantia and Avera acquisitions on September 19, 2019 and November 5, 2019, respectively, the Company recorded goodwill of $357.0 million. In connection with the Cavium acquisition on July 6, 2018, the Company recorded goodwill of $3.5 billion during fiscal 2019 and reduced goodwill by $3.0 million during fiscal 2020 in connection with measurement period adjustments, which were primarily related to changes in estimates related to finalizing Cavium’s 2018 U.S. tax return. See “Note 3 - Business Combinations” for further discussion of the acquisitions.

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 2020 did not result in any impairment charge.

During the year ended February 1, 2020 the Company acquired $572.0 million of intangible assets associated with the Aquantia and Avera acquisitions as follows (in thousands, except for weighted-average useful life as of acquisition date):


	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

During the year ended February 2, 2019, in connection with the Cavium acquisition, the Company acquired $2.7 billion of intangible assets. As of February 2, 2019, net carrying amounts are as follows (in thousands, except for weighted-average remaining amortization period):


	February 2, 2019
	Gross Carrying Amounts		Accumulated Amortization and Write-Offs		Net Carrying Amounts		Weighted-average remaining amortization period (years)
Developed technologies	$	1,743,000	$	(134,167)	$	1,608,833	7.10
Customer contracts and related relationships	465,000		(45,939)		419,061		8.42
Trade names	23,000		(3,212)		19,788		3.85
Total acquired amortizable intangible assets	2,231,000		(183,318)		2,047,682		7.34
IPR&D	513,000		—		513,000		n/a
Total acquired intangible assets	$	2,744,000	$	(183,318)	$	2,560,682

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 $368.1 million, $183.3 million and $3.6 million during the years ended February 1, 2020, February 2, 2019 and February 3, 2018 respectively. The following table presents the estimated future amortization expense of acquired amortizable intangible assets as of February 1, 2020 (in thousands):