Can you still buy IOC stock and be entitled to the CVR?

[MRP]

Yes. As long as you can still buy IOC shares you can get the CVR. The CVR is not structured like a dividend which has a cutoff date (ex-div) then continues to trade without the right to the dividend (or CVR). On the closing date of the merger all IOC shares will turn into either 1. Cash + CVR or 2. OSH shares + CVR and there will be no IOC shares remaining.

IOC will not trade in absence of the CVR right at any time unless they materially alter the deal.