Stock price when the opinion was issued
From today's price, $5.50 is in play. As a shareholder, you have to decide if it's worth holding onto your shares to get your $95 per share. There is a chance that the FTC is successful in challenging the US court order, in which case you'd want to exit now. He'd probably take his money and go, as there's a lot to be said for certainty.
MSFT will likely appeal and likely lose. The deal is probably dead. Also, the EU will weigh in. There's a $3 billion break-up fee for MSFT to pay ATVI.