The Company’s lease portfolio primarily comprises operating leases for office, laboratory, and manufacturing space. These leases contain various rent abatement periods, after which they require monthly lease payments that may be subject to annual increases throughout the lease term. Certain leases include options to extend the term. The renewal option is considered in the remaining lease term for the lease only when the Company is reasonably certain it will renew the lease. Certain leases provide the Company with the right to make tenant improvements, including the addition of laboratory space or build-out of manufacturing capabilities, and include a lease incentive allowance.

In June 2022, the Company entered into a lease agreement for 79,565 square feet of office, laboratory, and manufacturing space located in Bothell, Washington (the Bothell facility). The initial term of the lease expires in February 2039, with the option to extend the lease for up to three additional five-year terms. The lease agreement also provides for up to $19.9 million for reimbursement of tenant improvements, as well as an additional $8.0 million loan for tenant improvements, available at the Company’s election, which the Company would be obligated to repay to the landlord monthly over the initial term of the lease with interest at a rate of 6.5% per year (the Tenant Improvement Loan). The Company elected to receive the Tenant Improvement Loan in the second quarter of 2024. As of June 30, 2024, $0.3 million was included in accrued expenses and other current liabilities and $7.3 million was included in other non-current liabilities. The Company is obligated to pay base rent of approximately $68.8 million over the initial term of the lease. In accordance with the lease agreement, the Company has obtained a letter of credit in the amount of $1.6 million.

In April 2024, the Company amended the terms of certain agreements for its vivarium spaces in Cambridge, Massachusetts and South San Francisco, California, resulting in these agreements no longer requiring recognition on the balance sheet. In the second quarter of 2024, the Company derecognized the remaining balances related to the right-of-use asset and lease liability of $6.4 million and $6.2 million, respectively.

The following table contains additional information related to the Company’s operating leases:


Location	Use	Approximate Square Footage	Commencement Dates	Expiration Dates
Seattle, WA	Office/Laboratory	48,000	March 2019 to September 2020	December 2026 to April 2028
Cambridge, MA	Office/Laboratory	56,000	March 2019 to January 2020	June 2027 to February 2028
South San Francisco, CA	Office/Laboratory	99,000	December 2019 to April 2022	April 2030
Rochester, NY	Office/Laboratory	3,000	January 2022	January 2025
Bothell, WA	Office/Laboratory/Manufacturing	80,000	January 2023	January 2039

Throughout the term of each lease agreement, the Company is responsible for paying, in addition to base rent, certain operating costs, such as common area maintenance, taxes, utilities, and insurance. These additional charges are considered variable lease costs and are recognized in the period in which the costs are incurred.

The following table summarizes the Company’s lease costs:


	Three Months Ended June 30,				Six Months Ended June 30,
	2024		2023		2024		2023
	(in thousands)
Operating lease cost	$	4,469	$	6,981	$	9,088	$	14,042
Short-term lease cost		1,189		-		2,551		-
Variable lease cost		2,088		1,929		4,102		3,911
Total lease cost	$	7,746	$	8,910	$	15,741	$	17,953

As of June 30, 2024, the weighted-average remaining lease term was 9.7 years, and the weighted-average incremental borrowing rate was 11.4%.

The following table reconciles the Company’s undiscounted operating lease cash flows by fiscal year to the present value of the operating lease liabilities as of June 30, 2024 (in thousands):


2024 (remaining 6 months)	$	8,863
2025		21,768
2026		22,472
2027		19,899
2028		15,226
2029 and thereafter		93,495
Total undiscounted lease payments		181,723
Less: imputed interest		(83,001	)
Less: tenant improvement allowances		(165	)
Present value of operating lease liabilities		98,557
Less: current portion of operating lease liabilities	$	(9,998	)
Operating lease liabilities, net of current portion	$	88,559