15. Commitments and Contingencies

Leases

The Company’s lease portfolio includes leases for our corporate headquarters, office spaces, and a cell manufacturing facility. 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. At December 31, 2022, the Company had operating lease liabilities of $24.0 million and right of use assets of $20.0 million, which are included in the Company’s Consolidated Balance Sheet.

The Company recognizes rent expense on a straight-line basis over the non-cancellable lease term. Rent expense for the years ended December 31, 2022 and 2021 was $2.0 million and $2.1 million, respectively. The components of lease cost are as follows:

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The following tables summarize quantitative information about the Company’s operating leases:

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License Agreements

The Company has undertaken to make contingent milestone payments to the licensors of its portfolio of drug products and candidates. In addition, the Company shall pay royalties to such licensors based on a percentage of net sales of each drug candidate following regulatory marketing approval. For additional information on future milestone payments and royalties, see Note 7.

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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. The Company and its subsidiaries and partner companies also provide indemnification of contractual counterparties (sometimes without monetary caps) to clinical sites, service providers and licensors.

Legal Proceedings

In the ordinary course of business, the Company and its subsidiaries 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.