Abstract: A deadbolt assembly adapted for use with automatic door openers having a movable carriage power driven on a track mounted above the door. A lift arm connects the carriage to the door which swings the door up and down about a horizontal axis in response to movement of the carriage. A deadbolt shaft reciprocates within a sleeve which is secured to the lower inside portion of the door. The shaft locks the door when closed by engagement with a lock opening. A cable connects the shaft to the carriage so that the shaft is lifted out of the opening as the carriage moves to lift the door. A slotted bracket connection between the door and lift arm provides a lost motion action to delay door movement until the shaft is out of the opening. In an alternative embodiment, the lift arm includes a free end at the bracket connection. The door connection includes slots which allow the free end to extend beyond the bracket and engage a door header opening after the door is closed.