Inverted
mmmmmm wine
Same design as the Airbus. It's a certification thing.
The FCOM for the Airbus and the FH for the 737 make no mention of it. Seems pretty crazy that all somebody has to do is depressurize an aircraft to get the entire cockpit security door to open. NTSB said that Boeing is going to update the manual to reflect this.
I am also not aware of it being a design certification but I believe you.