Originally posted by: SDShamshel
I don't think Kisame was a part of the coup on Mizukage, seeing as Zabuza was the leader of that operation, and I doubt Kisame who is more than likely more powerful than Zabuza would let someone weaker than him lead.

I say more than likely because, well, let's look at the other Akatsuki members we know of so far: Itachi and Orochimaru.

It's safe to say Akatsuki is a pretty exclusive club.
they have already mentioned that all of the 7 katana mist shinobi was part of it and they do not state that zabuza was the leader. also kisame says himself that he was one of the 7 katan mist shinobi and all of them was part of the attack at the fuedal lord.