See, that's the thing, it has nothing to do with the light socket or bulb socket.
It is a 3 prong socket with a 3 prong plug, which is smaller than a type M.
The one office has sockets built into the building ceiling, there is 1 of them every say 2-4 ceiling panels (there is A LOT of them). The other office has the sockets at the end of the cables going to the DB board scattered in the roof.
The plug top is connected to 1200x600 luavre lights at one of the offices. The other office has 600x600 light panels and the same plug tops.