As of June 30, 2019, the Company has operating leases recorded on its balance sheet for approximately 70,500 square feet of office and lab space in three separate facilities in South San Francisco, California (the “Existing Facilities”). All of the lease agreements associated with the Existing Facilities expire on or before April 2020 and there are no options to extend the leases. The Company does not plan to cancel the existing lease agreements for its Existing Facilities prior to their respective expiration dates. The Company does not have any leases that would be classified as finance leases.

Information related to operating leases as of June 30, 2019 and upon adoption of ASC 842 on January 1, 2019 is as follows (in thousands, except for percentages and years).

	June 30, 2019			January 1, 2019
Assets
Operating lease right-of-use assets	$	1,756		$	1,940

Liabilities
Operating lease liabilities - current	$	1,831		$	2,126
Operating lease liabilities - noncurrent		—			—
	$	1,831		$	2,126

Weighted average remaining lease term (years)		0.7			1.0
Weighted average discount rate		6	%		6	%

Information related to operating lease activity during the six months ended June 30, 2019 follows (in thousands):

	Six Months Ended
	June 30, 2019
Operating lease right-of-use assets obtained in exchange for lease obligations	$	1,095

Operating lease rental expense	$	1,415

Operating lease payments	$	1,528

Future annual payments of operating lease liabilities as of June 30, 2019 are as follows (in thousands):

Year ending December 31:	Amount
2019 (six months remaining)	$	1,478
2020		387
Total future lease payments		1,865
Less: imputed interest		(34	)
Total operating lease liabilities	$	1,831

In September 2018, the Company entered into a noncancelable operating lease (the “Lease”) for approximately 129,800 square feet of space in Brisbane, California (the “New Facility”). The date on which the Company will record the ROU asset and lease liability on its balance sheet (the “Commencement Date”), as well as when it becomes responsible for paying rent under the Lease, will be the date the premises are ready for occupancy, currently anticipated to be January 2020. The Lease expires 10 years after the Commencement Date. The Lease grants the Company an option to extend the Lease for an additional 10-year period. Future minimum rental payments under the Lease during the 10-year term are $93.2 million in the aggregate. The Lease further provides that the Company is obligated to pay to the landlord certain costs, including taxes and operating expenses.

In September 2018, the Company provided a standby letter of credit of $1.9 million as security for its obligations under the Lease. This standby letter of credit, together with standby letters on Existing Facilities, are included on the balance sheet in prepaid expenses and other current assets and in restricted cash and other.

Future annual minimum operating lease payments due under the Lease for the New Facility are as follows (in thousands):

Year ending December 31:	Amount¹
2019 (six months remaining)	$	—
2020		5,454
2021		8,461
2022		8,757
2023		9,063
Thereafter		61,444
Total	$	93,179

Future annual minimum lease payments for operating leases as of December 31, 2018 were as follows (in thousands):

Year ending December 31:	Amount
2019		2,752
2020		5,831
2021		8,461
2022		8,757
2023		9,063
Thereafter		61,444
Total		96,308

The adoption of ASC 842 did not materially affect the amount or timing of operating lease rent expense to be recognized during the year ended December 31, 2019 as compared to accounting under the prior guidance. Operating lease rent expense, which is included in operating expenses on the Company’s condensed consolidated statements of operations and comprehensive loss, was $0.7 million and $0.6 million for the three months ended June 30, 2019 and 2018, respectively, and $1.4 million and $1.0 million for the six months ended June 30, 2019 and 2018, respectively. The operating leases require the Company to share in prorated operating expenses and property taxes based upon actual amounts incurred; those amounts are not fixed for future periods and, therefore, are not included in the future commitments listed above.