Oustanding shares will always be the same...
In the grey markets, we can see the bids/asks.
When one sells a stock, it doesn't mean it goes in limbo...there has to be a buyer on the other side, which is why the outstanding shares always remain the same. The only way the outstanding shares changes is if the company issues additional shares, does a stock split or reverse stock split, or buys back shares of stock. These are the most common ways the numbers of shares outstanding changes.