I read a post once from someone asking whether a failed invasion would result in the loss of planet quality, and the answer was no of course but recently i invaded a planet and it produced a perfect draw 0-0.
As you might expect the invasion screen said "invasion foiled" and i didn't get the planet but strangely enough i recieved some dialouge afterwards saying that the quality of the "captured" planet had been reduced (due to the invasion tactic).
I would of put this as a bug but i think its a pretty fair and likely scenario in a draw,
what do you guys think?