I don't see this fixed in 1.02's notes, so adding it here. This is game breaking.
There appears to be a negative integer? overflow causing the AI to give you everything they have.
On Insane Maps at least, add enough colonies from the AI side to the bargain...after enough "no", it will suddenly flip over to saying "you are so generous". The result is that you can simply ask the AI for all their colonies, their ships, their money and their tech...
I must say it is pretty hilarious but it is a chore to tell myself not to spoil my game when this is there...haha
Hey if you want to conquer the universe, simply ask...nicely...