Balance Sheets Components

12 Months Ended

Dec. 31, 2021

Balance Sheet Related Disclosures [Abstract]

4. Balance Sheets Components

Accounts Receivable, net

Accounts receivable, net consisted of the following:


	As of
	December 31, 2021			December 31, 2020
	(in thousands)
Accounts receivable, gross	$	38,426		$	23,970
Allowance for credit losses		(50	)		(50	)
Accounts receivable, net	$	38,376		$	23,920

Inventory

Inventory consisted of the following:


	As of
	December 31, 2021		December 31, 2020
	(in thousands)
Raw materials	$	1,841	$	435
Work in progress		16,963		10,184
Finished goods		4,826		1,731
Total inventories	$	23,630	$	12,350

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following:


	As of
	December 31, 2021		December 31, 2020
	(in thousands)
Advance to suppliers	$	—	$	853
Prepaid expenses		2,398		1,074
Other current assets		2,078		722
Total prepaid and other current assets	$	4,476	$	2,649

Property and Equipment, Net

Property and equipment, net consisted of the following:


	As of
	December 31, 2021			December 31, 2020
	(in thousands)
Lab and manufacturing equipment	$	44,283		$	21,958
Computer equipment		1,977			1,121
Furniture and fixtures		433			237
Construction in progress		7,100			638
Leasehold improvements		5,211			4,134
		59,004			28,088
Accumulated depreciation		(21,102	)		(16,380	)
Total property and equipment, net	$	37,902		$	11,708

Depreciation expense related to property and equipment was $5.7 million, $3.7 million, and $3.3 million for the years ended December 31, 2021, 2020 and 2019, respectively.

Intangible Assets, Net

Intangible assets, net consisted of the following:


	As of
	December 31, 2021							December 31, 2020
	(in thousands)
	Gross Assets		Accumulated Amortization			Net Assets		Gross Assets		Accumulated Amortization			Net Assets
	(in thousands)
Internal use software	$	9,434	$	(8,633	)	$	801	$	9,377	$	(8,312	)	$	1,065
Purchased intangibles		11,703		(6,527	)		5,176		5,663		(4,659	)		1,004
Intangible assets	$	21,137	$	(15,160	)	$	5,977	$	15,040	$	(12,971	)	$	2,069

Amortization expense for intangible assets was $2.2 million, $2.7 million, and $4.9 million, for the years ended December 31, 2021, 2020 and 2019, respectively. During the year ended December 31, 2021, the Company purchased and capitalized software costs of $6.0 million to support research and development efforts. During the year ended December 31, 2020, the Company recorded impairment charges of $1.0 million related to capitalized cost of software that was within the development phase and was being developed solely to meet the Company’s internal needs. The impairment charge was recorded as research and development expense in the consolidated statement of operations.

As of December 31, 2021 and 2020, the Company had $0.8 million and $0.7 million, respectively, of intangibles that were still in development stage and were not being amortized. The estimated aggregate future amortization expense for intangible assets in development stage and subject to amortization as of December 31, 2021 is summarized as below:


	As of
	December 31, 2021
	(in thousands)
2022	$	2,277
2023		2,207
2024		1,311
2025		168
2026		14
	$	5,977

Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following:


	As of
	December 31, 2021		December 31, 2020
	(in thousands)
Accrued payroll and related benefits	$	7,237	$	5,362
Deferred non-recurring engineering services		5,666		-
Revenue reserves		4,517		3,063
Short term lease liability		1,336		1,264
Accrued customer rebates		784		380
Other accrued expenses		4,742		2,894
Total accrued expenses and other current liabilities	$	24,282	$	12,963