v3.23.2
Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2023
Jun. 30, 2022
Operating activities    
Net loss $ (164,824) $ (186,580)
Adjustments to reconcile net loss from operations to net cash used in operating activities:    
Depreciation and amortization 3,597 4,769
Stock-based compensation expense 21,876 26,675
Net (accretion of discount) amortization of premium on marketable securities (5,738) 1,382
(Gain) loss on disposal of property and equipment (150) 10
Non-cash operating lease expense 5,263 4,919
Changes in operating assets and liabilities:    
Accounts receivable, net (45) (1,598)
Inventory (7,179) (4,060)
Other receivables 0 1,674
Prepaid expenses and other current and non-current assets 2,103 (3,556)
Accounts payable (6,837) (7,243)
Accrued expenses and other current liabilities (1,161) (3,584)
Operating lease liabilities (6,713) (5,551)
Other non-current liabilities (2,123) 779
Net cash used in operating activities (161,931) (171,964)
Investing activities    
Purchases of marketable securities (232,486) (607,747)
Proceeds from maturities and sales of marketable securities 337,453 668,717
Purchases of property and equipment (396) (4,730)
Proceeds from sale of equipment 150 0
Net cash provided by investing activities 104,721 56,240
Financing activities    
Payments on financing lease obligations 0 (164)
Net proceeds from stock option exercises and employee stock purchase plan 2,704 1,305
Net cash provided by financing activities 2,704 1,141
Net change in cash and cash equivalents (54,506) (114,583)
Cash and cash equivalents at beginning of the period 139,259 203,126
Cash and cash equivalents at end of the period 84,753 88,543
Supplemental disclosure of non-cash investing and financing transactions    
Additions to property and equipment in accounts payable and accrued expenses 6 11
Cash taxes paid $ 801 $ 1,842