It has not been said yet where the 500M shares are coming from. But since SB is CEO of both, he can pretty much do what he wants as long as it is legal and reported. He bought the empty shell of IGPK out of his own pocket last year, and gave himself (TGGI) the 540M shares. (IGPK came with some hefty, unexpected debt, which has slowed things down a lot.)
At least he is now finally doing SOMETHING with TGGI...