The claim of the non-debtor party to a contract or lease that is rejected by the debtor. Rejection of an executory contract or unexpired lease is treated as a prepetition breach of the contract or lease by the debtor, entitling the non-debtor party to a damages claim for the breach. The amount of some rejection claims is subject to a statutory cap under Section 502(b).
Bankruptcy Code § 503(b)(6). See also Landlord Claim, Rejection of Executory Contracts and Unexpired Leases.