Leases

12 Months Ended

Dec. 31, 2024

7. Leases

In May 2020, the Company entered into a lease agreement for a cell therapy manufacturing facility in Framingham, Massachusetts, or the Framingham Lease, for clinical and commercial production of the Company’s investigational cell therapy product candidates. The Framingham Lease expires in March 2036 and the Company has an option to extend the term of the lease for two additional seven-year periods. The right-of-use asset and corresponding lease liability does not include the additional seven-year periods under the renewal option as the Company is not reasonably certain to exercise that option.

In July 2020, the Company entered into a lease agreement for an office and laboratory facility in Boston, Massachusetts, with a commencement date of June 1, 2021, or the 2020 Lease. At lease commencement, the Company recorded a right-of-use asset of $149.8 million and a corresponding operating lease liability of $147.9 million. Tenant incentives of $49.2 million were recorded as a reduction to the operating lease asset and liability at lease commencement. The lease expires in March 2034 and the Company has an option to extend the term of the lease for two additional five-year periods. The right-of-use asset and corresponding lease liability does not include the additional five-year periods under the renewal option as the Company is not reasonably certain to exercise that option.

The Company also rents certain office space in Zug, Switzerland, on a short-term basis for which a right-of-use asset and liability are not recorded, in accordance with the practical expedient elected.

The Company has embedded leases in certain research and license agreements for which the Company has recorded a right of use asset and liability. These arrangements are not significant in comparison to the Company’s total operating lease assets and liabilities.

The Company identified and assessed the following estimates in recognizing the right-of-use asset and corresponding liability:

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Expected lease term: The expected lease term includes noncancelable lease periods and, when applicable, periods covered by an option to extend the lease if the Company is reasonably certain to exercise that option, as well as periods covered by an option to terminate the lease if the Company is reasonably certain not to exercise that option.

•

Incremental borrowing rate: As the discount rates in the Company’s leases are not implicit, the Company estimated the incremental borrowing rate based on the rate of interest the Company would have to pay to borrow a similar amount on a collateralized basis over a similar term.

The following table summarizes the lease assets and liabilities as of December 31, 2024 and 2023 (in thousands):


	As of December 31,
	2024		2023
Assets
Operating lease assets	$	143,461	$	153,993
Total lease assets		143,461		153,993
Liabilities
Current
Operating lease liabilities		17,288		15,625
Non-current
Operating lease liabilities, net of current portion		206,405		223,007
Total lease liabilities	$	223,693	$	238,632

The following table summarizes operating lease costs included in research and development and general and administrative expense, as well as sublease income for the years ended December 31, 2024, 2023 and 2022 (in thousands):


	Years Ended December 31,
	2024			2023			2022
Operating lease costs	$	24,417		$	25,870		$	34,896
Short-term lease costs		40			—			824
Variable lease costs		12,364			14,387			11,882
Sublease income		(573	)		(137	)		—
Net lease cost	$	36,248		$	40,120		$	47,602

The following table summarizes the maturity of undiscounted payments due under lease liabilities and the present value of those liabilities as of December 31, 2024 (in thousands):


	Total
2025		29,416
2026		29,468
2027		28,704
2028		28,158
2029		27,314
Thereafter		151,570
Total	$	294,630
Present value adjustment		(70,937	)
Present value of lease liabilities	$	223,693

The following table summarizes the lease term (in years) and discount rate for operating leases as of December 31, 2024 and 2023:


	As of December 31,
	2024			2023
Weighted-average remaining lease term		9.8			10.8
Weighted-average discount rate		5.9	%		5.9	%

The following table summarizes the cash paid for amounts included in the measurement of lease liabilities for the years ended December 31, 2024, 2023 and 2022 (in thousands):


	Years Ended December 31,
	2024			2023			2022
Cash paid for amounts included in measurement of lease liabilities:
Operating cash flows used in operating leases	$	(28,949	)	$	(27,310	)	$	(17,004	)
Operating lease non-cash items:
Right-of-use assets increased through lease modifications and reassessments		525			2,660			1,208
Right-of-use assets obtained in exchange for operating lease liabilities		243			7,552			—
Leasehold improvements paid directly by landlord		—			—			19,252