Abstract: A bi-swing warehouse door latch system installs an electro-mechanical lock horizontally in the door casings overhead. Each has two catches to drop down on either side of the door. The doors are allowed to swing open when the respective catches are unlatched by a solenoid. The doors are not allowed to swing open when the respective catches are held latched by another solenoid and a teeter arm. Battery powered models produce brief pulses to put the catches in their locked states or unlocked states using a capacitor to store enough energy after power is lost to kick the solenoids. Utility powered versions can be configured to automatically relax into locked or unlocked states when power is lost. The doors are controlled to unlock when those with authorized access are recognized.