A question for the more financially minded around here: How much of an impact would Cuban's sale of the stock have made on the price? As in, had he waited until

A question for the more financially minded around here: How much of an impact would Cuban's sale of the stock have made on the price? As in, had he waited until their announcement, then sold all of his (largest minority) share, how much of a price deflation could have been expected? I imagine if that drop were large enough, he'd at least have an argument that he shouldn't need to pay all of the $750k back.