15. Commitments and Contingencies

Most of the Company's lease liabilities result from the lease of its New York City, NY office, which expires in 2031, and Mustang's Worcester, MA cell processing facility lease, which expires in 2026. Such leases do not require any contingent rental payments, impose any financial restrictions, or contain any residual value guarantees. Certain of the Company's leases include renewal options and escalation clauses; renewal options have not been included in the calculation of the lease liabilities and right of use assets as the Company is not reasonably certain to exercise the options. The Company does not act as a lessor or have any leases classified as financing leases. On September 30, 2020, the Company had operating lease liabilities of $24.6 million and right of use assets of $20.3 million, which were included in the Condensed Consolidated Balance Sheet.

During the three and nine months ended September 30, 2020 and 2019, the Company recorded the following as lease expense, which was recorded in general and administrative expense on the Company's Condensed Consolidated Statement of Operations:

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The following tables summarize quantitative information about the Company's operating leases, under the adoption of Topic 842, Leases:

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Indemnification

In accordance with its certificate of incorporation, bylaws and indemnification agreements, the Company has indemnification obligations to its officers and directors for certain events or occurrences, subject to certain limits, while they are serving at the Company’s request in such capacity. There have been no claims to date, and the Company has director and officer insurance to address such claims. Pursuant to agreements with clinical trial sites, the Company provides indemnification to such sites in certain conditions.

Legal Proceedings

In the ordinary course of business, the Company may be subject to both insured and uninsured litigation. Suits and claims may be brought against the Company by customers, suppliers, partners and/or third parties (including tort claims for personal injury arising from clinical trials of the Company’s product candidates and property damage) alleging deficiencies in performance, breach of contract, etc., and seeking resulting alleged damages.