In June 2018, the Company signed a lease agreement to lease approximately 105,000 square feet in office and laboratory space in South San Francisco which serves as the Company’s headquarters (the Headquarters). The lease expires in 2029 with an option to renew for a period of ten years. The landlord paid for $15.7 million of tenant improvements. In connection with the lease, the Company entered into a letter of credit arrangement in the amount of $1.5 million as collateral for the lease, which is classified as restricted cash on the consolidated balance sheets. In October 2020, the Company signed a lease agreement to lease approximately 18,700 square feet of office and laboratory space in Newark, California. The lease term ends on February 6, 2028 with an option to extend for an additional five years. The landlord is obligated to pay for up to $0.4 million of tenant improvements. The measurement of the lease liabilities for the leases excludes the options to extend the term

of the lease as such extensions are not reasonably certain to occur. Variable lease costs for all of the Company’s leases consist of operating expenses for the spaces.

In May 2019, the Company entered into an agreement to sublease approximately 25,000 square feet of the Headquarters, which was amended to approximately 23,600 square feet in December 2020. This Sublease expired in November 2021.

In November 2021, the Company entered into an agreement to sublease approximately 7,100 square feet of the Headquarters, which was amended in May 2022 to include an additional space of 13,150 square feet. The 7,100 square feet of space subleased expired in December 2022 and the additional space of 13,150 expired in November 2023. In October 2023, the Company entered into a second amendment to sublease approximately 13,250 square feet of the Headquarters. This sublease will expire in November 2024.

In February 2023, the Company entered into an agreement to sublease approximately 9,300 square feet of the Headquarters. This sublease will expire in February 2025. The sublessee pays its proportionate share of operating expenses for the space.

The components of lease expense were as follows:


				December 31,
	2023			2022			2021
	(In thousands)
Operating lease cost	$	6,626		$	6,638		$	6,204
Variable lease cost		3,149			2,785			3,046
Sublease income and reimbursement of variable lease cost		(2,482	)		(1,872	)		(2,141	)
Total	$	7,293		$	7,551		$	7,109

As of December 31, 2023, the weighted-average remaining lease term for operating leases was 5.2 years and the weighted-average discount rate was 8.5%. Cash paid for amounts included in the measurement of lease liabilities for the year ended December 31, 2023, 2022, and 2021 was $8.4 million, $8.2 million, and $7.9 million, respectively, was included in net cash used in operating activities in our consolidated statements of cash flows.

The following are the lease payments owed under the Company’s operating leases as of December 31, 2023:


	(In thousands)
2024	$	8,855
2025		9,161
2026		9,477
2027		9,804
2028		8,969
Thereafter		2,209
Total undiscounted lease payments		48,475
Less: Present value adjustment		(9,557	)
Total lease liability	$	38,918