The Company determines if an arrangement is a finance lease, operating lease or short-term lease at inception. During the periods presented, the Company was party to various non-cancellable office and laboratory space operating leases and short-term leases. Short-term leases are not subject to recognition of an ROU asset or liability or straight-line lease expense requirements.

As of December 31, 2023, the Company’s ROU assets and liabilities related to the operating lease for the Company headquarters are as follows (in thousands):


ROU assets	$	8,271

Lease liabilities, current portion	$	3,639
Lease liabilities, net of current portion	6,213
Total lease liabilities	$	9,852

As of December 31, 2023, maturities of the lease liabilities due under the operating lease are as follows (in thousands):


Year ending December 31,
2024	$	3,697
2025	3,854
2026	3,639


Total lease payments	11,190
Less imputed interest	(1,338)
Total operating lease liabilities	9,852
Less lease liabilities, current portion	(3,639)
Lease liabilities, net of current portion	$	6,213


	Year Ended December 31,
	2023			2022			2021
Cash paid included in operating cash flows	$	3,328		$	1,762		$	234
Weighted-average remaining lease term (in years)	2.9			3.9			4.9
Weighted-average discount rate	5.9		%	5.5		%	5.5		%

Lease cost was $3.0 million, $2.7 million and $0.9 million for the years ended December 31, 2023, 2022, and 2021, respectively. Short-term and variable lease costs were immaterial for all periods presented.

Liabilities for loss contingencies arising from claims, assessments, litigation, fines, penalties and other sources are recorded when it is probable that a liability has been incurred and the amount can be reasonably estimated. There are no such matters currently outstanding for which any liabilities have been accrued.

The Company enters into contracts in the normal course of business for contract research services, contract manufacturing services, professional services, and other services and products for operating purposes. These contracts may include certain provisions that could require payments for early termination. The amount of any such termination payments will vary depending on the timing of the termination and the specific terms of the

contract. Further, the Company has entered into various contracts to acquire contractual rights to licensed technology, some of which may require the Company to make additional milestone payments upon initiation of a pivotal trial and U.S. Food and Drug Administration approval.