The Company’s long-term property lease with Alexandria for its corporate headquarters in San Francisco, California, had an initial term of 15 years, scheduled to expire in 2023. The original lease was accounted for as a finance lease upon adoption of ASC 842, Leases (“ASC 842”), at January 1, 2019.

On June 1, 2021, the Company entered into an amendment with Alexandria to extend the lease to 2028 (“Lease Amendment”). Under the terms of the Lease Amendment, the Company has two optional rights to each extend the lease for an additional five years. The lease contract provides for a fixed annual rent, with scheduled increases of two percent that occur on each anniversary of the rent commencement date through 2023, and with scheduled increases of three percent that occur on each anniversary of the rent commencement date through 2028. This lease requires the Company to pay all costs of ownership, operation, and maintenance of the premises, including without limitation all operating costs, insurance costs, and taxes.

Company determined that the Lease Amendment was a lease modification, effective June 1, 2021, and thus reassessed the lease classification, remeasured the related lease liability using an updated discount rate, and adjusted the related right-of-use asset under the lease modification guidance under the ASC 842. Accordingly, on June 1, 2021, the Company determined that the modified lease be accounted for as an operating lease, and therefore derecognized the previous finance lease right-of-use asset of $24.6 million and the related finance lease liability of $32.6 million, and recognized an operating lease right-of-use asset of $93.2 million and the related operating lease liability of $101.2 million. Starting June 1, 2021, the cash payment related to this lease was classified as an operating activity, the impact of which was approximately $7.9 million to the consolidated statement of cash flow for the year ended December 31, 2021.

During the first quarter of 2021, after FibroGen Beijing’s previous long-term lease agreement expired, the Company entered into a new lease agreement with the landlord for the same pilot plant located in Beijing Yizhuang Biomedical Park of BDA. The new lease term is five year, scheduled to expire in 2026, and is treated as an operating lease. Accordingly, the Company recorded $3.4 million in the operating right-of-use assets and total operating lease liabilities, respectively. The lease contract provides for fixed quarterly rent payments, and requires the Company to pay operating and maintenance costs.

The Company currently has several additional real estate leases for office spaces in Shanghai and Beijing, China, which are treated as operating leases. These leases have lease terms ranging from one to five years, expiring in 2023. These lease contracts provide for fixed quarterly rent payments, and require the Company to pay operating and maintenance costs, and a fixed amount for property management fees.

In addition, the Company has several immaterial lease arrangements in China and U.S. for office equipment, scientific devices and automobile leases, with contracted lease terms ranging from one to five years, treated as finance leases or operating leases, respectively.

The Company’s lease assets and related lease liabilities were as follows (in thousands):

		December 31,
	Balance Sheet Line Item	2021			2020
Assets
Finance:
Right-of-use assets cost		$	2,165		$	50,477
Accumulated amortization			(1,404	)		(20,871	)
Finance lease right-of-use assets, net	Finance lease right-of-use assets		761			29,606
Operating:
Right-of-use assets cost			100,912			3,934
Accumulated amortization			(9,800	)		(1,891	)
Operating lease right-of-use assets, net	Operating lease right-of-use assets		91,112			2,043
Total lease assets		$	91,873		$	31,649

Liabilities
Current:
Finance lease liabilities	Finance lease liabilities, current	$	11		$	12,330
Operating lease liabilities	Operating lease liabilities, current		10,944			1,188
Non-current:
Finance lease liabilities	Finance lease liabilities, non-current		3			25,391
Operating lease liabilities	Operating lease liabilities, non-current		88,776			853
Total lease liabilities		$	99,734		$	39,762

		Years Ended December 31,
	Statement of Operations Line Item	2021			2020			2019
Finance lease cost:
Amortization of right-of-use assets	Cost of goods sold; Research and development; Selling, general and administrative expenses	$	4,639		$	10,369		$	10,307
Interest on lease liabilities	Interest expense		628			1,932			2,373
Operating lease cost	Cost of goods sold; Research and development; Selling, general and administrative expenses		10,722			1,151			891
Sublease income	Selling, general and administrative expenses		(1,271	)		(1,201	)		(1,385	)
Total lease cost		$	14,718		$	12,251		$	12,186

Supplemental cash flow information related to leases were as follows (in thousands):

	Years Ended December 31,
	2021			2020		2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	10,022		$	951	$	914
Operating cash flows from finance leases		629			1,896		2,196
Financing cash flows from finance leases		5,489			12,620		11,925
Non-cash: Right-of-use assets obtained in exchange for new lease liabilities:
Finance leases		450			662		49,909
Operating leases		3,585			1,072		2,736
Non-cash: Increase (decrease) resulting from lease modification:
Finance lease right-of-use assets		(24,654	)		—		—
Operating lease right-of-use assets		93,222			—		—
Finance lease liabilities, current		(12,587	)		—		—
Operating lease liabilities, current		9,221			—		—
Finance lease liabilities, non-current		(20,009	)		—		—
Operating lease liabilities, non-current	$	91,943		$	—	$	—

	December 31,
	2021			2020
Weighted-average remaining lease term (years):
Finance leases		1.1			2.9
Operating leases		6.8			1.8
Weighted-average discount rate:
Finance leases		4.64	%		4.39	%
Operating leases		4.75	%		4.74	%

Maturities of lease liabilities as of December 31, 2021 are as follows (in thousands):

Year Ending December 31,	Finance Leases			Operating Leases
2022	$	12		$	15,387
2023		3			13,469
2024		—			16,810
2025		—			18,205
2026		—			18,005
Beyond 2026		—			35,877
Total future lease payments		15			117,753
Less: Interest		(1	)		(18,033	)
Present value of lease liabilities	$	14		$	99,720