They do need to investigate, but guilt isn’t a forgone conclusion. The SEC has durable trade program you can enter into during a normal trade window that is allowed to make trades for you during the restricted trade window, but only based on preprogrammed instructions relying only on public values. So for example “as long as the stock value is over $300/share sell 50% of the shares I just vested this month”. The big requirement for this sort of program is that you can only alter it during open trade windows.
So if you had one of these set up during an open trade window and at the time you set it up didn’t have any knowledge of the hack (or other material inside information) and you later found out about the hack during a closed trade window I think it would be illegal to cancel the trade!
I’m not a lawyer though, and only briefly read about this program when deciding not to opt into one. So I may be missing critical details. Also we don’t actually know that is what happened, just that it is a way in which this could have been legal.
