This DB is about 1.5 million games the last time I checked so I wouldn't expect it to be error free. I have no idea where the DB here came from of it's an "original" (I think it is) so I can't say for sure if it has any sort of "integrity check" for games meeting one or more certain criterion such as the players are rated <2200, the game score has 1 or more illegal moves, etc. There should be some way for the DB here to be examined for games that don't belong in it, but that's only a guess on my part.
I'm using CB9 with a "BIG DB 2011" I've updated to inc 5.5 million games so far, and occasionally come across errors such as games with no moves or duplicate games.
I know I saw this a long time ago, but seriously, I came across it again, and it had me wondering why this game is in the masters database... http://www.chess.com/games/view?id=198942