Patent ID: 8567501

Claim:
An apparatus for selectively stimulating a formation within in a wellbore, the apparatus comprising: a housing connected to a fracturing string, the housing having a fracture port permitting fluid communication between an inner bore of the housing and an exterior of the housing, the housing including a fracture sleeve that is movable between an open position and a closed position, wherein the closed position prevents fluid communication between the inner bore and the exterior of the housing; and a ball seat assembly that is adapted to selectively engage the housing, the ball seat assembly comprising: a ball seat adapted to sealingly engage a ball having a predetermined diameter; a key connected to the ball seat, the key being adapted to selectively mate with a profile on the fracture sleeve; a lock sleeve connected to the ball seat, the lock sleeve being movable from an initial unlocked position to a locked position, the lock sleeve being biased to the locked position, in the locked position the lock sleeve being adapted to selectively retain the key in a mated position with the profile on the fracture sleeve.