In February 2015, the Company entered into a noncancelable operating lease for approximately 31,280 square feet of space used for its current laboratory and corporate headquarters. In April 2020, the Company extended the term of the lease through November 30, 2027. The lease includes an option to extend the term for a period of three years with rent payments equal to fair market rent. The Company determined the extension option is not reasonably certain to be exercised. The lease contains a leasehold improvement incentive and escalating rent payments. In May 2021, the Company amended the lease to expand the premises subject to the lease to include an additional 14,710 square feet of space (the “Expansion Lease”). The Expansion Lease expires on December 31, 2022 and has no option to extend the term.

In August 2019, the Company entered into a noncancelable operating lease for a co-located data center space. The lease expires on August 31, 2022 and includes an option to extend the term for a period of three years immediately following the expiration of the term with rent payments to be negotiated upon such a renewal. The Company determined the extension option is not reasonably certain to be exercised. In April 2020, the lease was modified to increase the data center space available for the Company’s use for the remainder of the lease term.

In August 2021, the Company entered into a noncancelable operating lease for approximately 100,000 square feet of space in Fremont, California to be used as the Company’s future corporate headquarters and expanded laboratory facility. The lease term is 13.5 years and commenced in June 2022. The Company gained early access to the premises upon entering the lease for the purpose of constructing and installing tenant improvements, for which the landlord has agreed to contribute up to approximately $15.5 million, $5.5 million of which has been received through June 30, 2022. Such contributions become payable only upon approval by the landlord of applications for payment and are accounted for as lease incentives once the Company has incurred costs and the amounts qualify for reimbursement by the landlord. The lease incentives are then recognized as reductions to lease expense over the remainder of the lease term. The lease expires on November 30, 2035 and includes two options to extend the term for a period of five-years per option with rent payments equal to fair market rent. The Company determined the extension options are not reasonably certain to be exercised. The lease also contains escalating rent payments.

The Company also has a noncancelable operating lease for approximately 5,100 square feet of space in Shanghai, China used for its China operations, which expires on June 30, 2024, as well as various other short-term leases.

	Three Months Ended June 30,				Six Months Ended June 30,
	2022		2021		2022		2021
Lease cost
Operating lease cost	$	2,174	$	769	$	4,348	$	1,421
Short-term lease cost		8		192		37		262
Variable lease cost		385		165		646		394
Total lease cost	$	2,567	$	1,126	$	5,031	$	2,077

As of June 30, 2022, the Company’s operating leases had a weighted-average remaining lease term of 12.0 years and a weighted-average discount rate of 6.6%. The Company’s discount rates are based on estimates of its incremental borrowing rate, as the discount rates implicit in the leases cannot be readily determined. Future lease payments under operating leases as of June 30, 2022 were as follows (in thousands):

	Amount
2022 (remaining six months)	$	1,980
2023		6,194
2024		6,802
2025		7,001
2026		7,217
2027 and thereafter		53,527
Total future minimum lease payments		82,721
Less: imputed interest		(26,245	)
Present value of future minimum lease payments		56,476
Less: current portion of operating lease liability		(4,640	)
Long-term operating lease liabilities	$	51,836

Cash paid for operating lease liabilities, included in cash flows from operating activities in the condensed consolidated statements of cash flows, for the six months ended June 30, 2022 and 2021, was $1.9 million and $1.4 million, respectively. Right-of-use assets obtained in exchange for new operating lease liabilities during the six months ended June 30, 2022 and 2021 were zero and $1.7 million, respectively.