B737 First Officer reports a company manager requesting the jumpseat after scheduled departure time. The reporter is informed after the flight that the manager was not authorized jumpseat access.

Narrative

Previous flight came in late. We had a full airplane with one off-line jumpseater. We were after push time when the Gate Agent told the Captain that there was a Manager that was requesting to ride the jumpseat. The Captain grabbed a page from his FOM and left the cockpit. I was busy contacting ATC for our wheels up time; which I had to get revised due to the boarding delay. The Captain and Manager came back and I do recall the Captain once again confirming that he was authorized to ride the jumpseat and he replied that he was. I quickly introduced myself and continued my preflight duties. I assumed since the Captain had his FOM and was working with the Gate Agent and the Manager that the issue of whether he was authorized was resolved. I just received a call from my Captain letting me know that he had talked to a Chief Pilot and that the manager was not authorized access to the cockpit. Although I was busy trying to get my duties accomplished and get the flight out close to on time; I should have stopped and confirmed this situation was completely resolved and legitimate. Either the Manager had false information on the access to the jumpseat or he was just plain lying to get on the flight and make it to our destination.