Balance Sheet Components

Property and Equipment, Net

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



	As of January 31, 2016			As of October 31, 2016
Test equipment	$	65,663		$	103,491
Computer, equipment and software	31,388			50,235
Furniture and fixtures	2,852			4,072
Leasehold improvements	4,935			9,902
Total property and equipment	104,838			167,700
Less: accumulated depreciation and amortization	(52,209		)	(85,612		)
Property and equipment, net	$	52,629		$	82,088

Depreciation and amortization expense was $8.5 million and $13.2 million for the three months ended October 31, 2015 and 2016 and $22.1 million and $34.9 million for the nine months ended October 31, 2015 and 2016, respectively.

Intangible Assets, Net

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



	As of January 31, 2016			As of October 31, 2016
Technology patents	$	9,125		$	10,125
Accumulated amortization	(2,145		)	(3,189		)
Intangible assets, net	$	6,980		$	6,936

Intangible assets amortization expense was $326,000 and $376,000 for the three months ended October 31, 2015 and 2016 and $978,000 and $1.0 million for the nine months ended October 31, 2015 and 2016. Due to the defensive nature of these patents, the amortization is included in general and administrative expenses in the condensed consolidated statements of operations.

As of October 31, 2016, expected amortization expense for intangible assets for each of the next five years and thereafter is as follows (in thousands):



Fiscal Years Ending January 31,	Estimated Future Amortization Expense
Remainder of 2017	$	376
2018	1,504
2019	1,504
2020	1,504
2021	1,504
Thereafter	544
Total	$	6,936

Accrued Expenses and Other Liabilities

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



	As of January 31, 2016		As of October 31, 2016
Sales and use tax payable	$	299	$	406
Accrued professional fees	3,044		3,256
Accrued marketing	2,684		6,908
Accrued travel and entertainment expenses	2,182		2,977
Income tax payable	1,791		974
Other accrued liabilities	4,076		6,024
Total accrued expenses and other liabilities	$	14,076	$	20,545