A surgical stapler includes a first elongate member having a distal portion that supports a plurality of staple-forming pockets, a second elongate member having a distal portion that supports a staple cartridge, and a clamp member movable from an open position to a closed position to releasably clamp the first and second elongate members together. A clamp lockout feature is supported by the first elongate member and is moveable between a lockout position in which the clamp lockout feature prevents closure of the clamp member, and a release position in which the clamp lockout feature permits closure of the clamp member. An actuating feature is supported by the second elongate member and is configured to actuate the clamp lockout feature from the lockout position to the release position in response to approximation of the distal portions of the first and second elongate members.
