The Company’s operating leases for its Cambridge, Andover and Burlington, Massachusetts and Dublin and Columbus, Ohio facilities provide for scheduled annual rent increases throughout each lease’s term. A summary of these leases are as follows:

In June 2013, the Company entered into a lease agreement (the “Cambridge Lease”) for its headquarters located in Cambridge, Massachusetts. In April and September 2018 and June 2019, the Company entered into the seventh, eighth, and ninth amendments, respectively, to its Cambridge Lease which extended the original term of the lease to September 30, 2025 and increased the total rental space to approximately 170,929 square feet.

In March and July of 2018, the Company entered into sublease agreements in Andover, Massachusetts, to lease a total of 23,102 square feet of office and lab space. These subleases expire in December 2020.

In November 2018, the Company entered into a sublease agreement in Burlington, Massachusetts, to lease 44,740 square feet of office and lab space. The sublease expires in January 2022.

In December 2018, the Company entered into lease agreements in Dublin and Columbus, Ohio, to lease 22,600 square feet and 77,679 square feet, respectively, of office and lab space. The leases expire in November 2019 and June 2026, respectively.

The adoption of ASC 842 resulted in the recognition of operating lease liabilities and ROU assets of $60.1 million and $42.5 million, respectively, on the Company’s balance sheet relating to its leases for its corporate headquarters and its office and lab space on the January 1, 2019 transition date. Further, the Company reclassified upon adoption $18.0 million of deferred rent which served to reduce the ROU assets recognized on the balance sheet, in accordance with the transition guidance.

As of September 30, 2019, operating lease assets were $39.5 million and operating lease liabilities were $57.3 million. Amounts related to financing leases were immaterial. The following table contains a summary of the lease costs recognized under Topic 842 and other information pertaining to the Company’s operating leases for the three and nine months ended September 30, 2019:

Operating Lease (in thousands)	For the three months ended September 30, 2019		For the nine months ended September 30, 2019
Lease cost
Operating lease cost		2,606		7,738
Variable lease cost		1,008		2,946
Total lease cost	$	3,614	$	10,684

Other information
Operating lease payments				7,606
Operating lease liabilities arising from obtaining ROU assets				—
Weighted average remaining lease term			5.7
Weighted average discount rate				7.50	%

Future minimum lease payments under the Company’s non-cancelable operating leases as of September 30, 2019, are as follows:

Maturity of lease liability (in thousands)	As of September 30, 2019
2019 (October - December)	$	2,809
2020		11,718
2021		12,890
2022		11,080
2023		11,230
Thereafter		21,126
Total minimum lease payments		70,853
Less: imputed interest		(13,516	)
Total operating lease liabilities	$	57,337
Included in the condensed consolidated balance sheet:
Current portion of lease liabilities within other current liabilities	$	7,596
Lease liabilities		49,741
Total operating lease liabilities	$	57,337

Future minimum lease payments under the Company’s non-cancelable operating leases as of December 31, 2018, are as follows:

Maturity of lease liability (in thousands)	As of December 31, 2018
2019	$	11,588
2020		11,395
2021		12,558
2022		10,757
2023		10,898
Thereafter		20,524
Total minimum lease payments	$	77,720