14. Commitments and Contingencies

Leases

New York, NY Sublease - Fortress

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On February 10, 2026, the Company entered into a sublease agreement with a third party to sublease all of its leased office space in New York, NY, consisting of approximately 23,000 square feet, under its existing lease with Sage Realty Corporation (the “Landlord”). The Company obtained the Landlord’s consent to the sublease, and the sublease commenced on March 15, 2026. The sublease expires on August 31, 2031.

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Pursuant to the sublease agreement, the Company expects to receive approximately $11.9 million in aggregate base rent payments over the term of the sublease. The Company remains primarily liable for the obligations under the original lease.

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For the three months ended March 31, 2026, the Company continued to recognize lease expense under the original lease agreement and recognized sublease income from the sublease commencement date of March 15, 2026. Sublease income is recognized on a straight-line basis over the sublease term. The Company has elected to present sublease income as a reduction of lease expense within the condensed consolidated statement of operations.

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Lease Termination – Mustang

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In February 2025, Mustang concurrently exited the lease of its manufacturing facility in Worcester, Massachusetts, relocating its corporate headquarters to 95 Sawyer Road, Waltham, Massachusetts, and divested certain fixed assets including furniture and equipment to AbbVie Bioresearch Center, Inc. for $1.0 million. In connection with the lease termination, Mustang recorded a net gain on lease termination of $0.4 million recorded in research and development expenses on the condensed consolidated statement of operations.

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During the three months ended March 31, 2026 and 2025, the Company recorded the following as lease costs for the periods presented:

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The following tables summarize quantitative information about the Company’s operating leases, under the adoption of ASC 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. 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.

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Legal Proceedings

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