Also known as a lock-out, shut-out or no-shop agreement. An agreement used to try to ensure that a party to a prospective transaction negotiates solely with a particular prospective transaction counterparty for an agreed period of time.

The aim of such an agreement is to provide some protection for the prospective counterparty against the risk that another party will outbid it, by providing it with a period in which to seek to negotiate a deal during which time the other party will not negotiate with other potential interested parties.