Balance Sheet Components

Inventory

Inventory consists of the following (in thousands):



	As of January 31, 2018		As of April 30, 2018
Raw materials	$	1,181	$	124
Finished goods	33,316		38,416
Inventory	$	34,497	$	38,540

Property and Equipment, Net

Property and equipment, net, consists of the following (in thousands):



	As of January 31, 2018			As of April 30, 2018
Test equipment	$	142,311		$	148,444
Computer equipment and software	72,329			82,102
Furniture and fixtures	5,363			5,611
Leasehold improvements	15,032			18,134
Total property and equipment	235,035			254,291
Less: accumulated depreciation and amortization	(145,893		)	(160,011		)
Property and equipment, net	$	89,142		$	94,280

Depreciation and amortization expense was $14.4 million and $16.0 million for the three months ended April 30, 2017 and 2018.

Intangible Assets, Net

Intangible assets, net, consist of the following (in thousands):



	As of January 31, 2018			As of April 30, 2018
Technology patents	$	10,125		$	10,125
Accumulated amortization	(5,068		)	(5,444		)
Intangible assets, net	$	5,057		$	4,681

Intangible assets amortization expense was $0.4 million for three months ended April 30, 2017 and 2018. The weighted-average remaining useful life of technology patents is 3.1 years. Due to the defensive nature of these patents, the amortization expense is included in general and administrative expenses in the condensed consolidated statements of operations.

As of April 30, 2018, future expected amortization expense for intangible assets is as follows (in thousands):



Years Ending January 31,	Estimated Future Amortization Expense
Remainder of 2019	$	1,128
2020	1,504
2021	1,504
2022	545
Total	$	4,681

Accrued Expenses and Other Liabilities

Accrued expenses and other liabilities consist of the following (in thousands):



	As of January 31, 2018		As of April 30, 2018
Taxes payable	$	4,052	$	3,790
Accrued marketing	5,928		4,703
Accrued travel and entertainment expenses	4,386		4,119
Other accrued liabilities	12,463		13,017
Total accrued expenses and other liabilities	$	26,829	$	25,629