The float could be zero and the stock price can still rise with none of the longs selling. Keep in mind that the movement of any stock is based upon supply and demand. Let's say for example that the entire O/S was in strong hands, meaning there are no available shares in the float for trading, and the company puts out some spectacular news showing some from of revenues coming in. You will have people look at the current share price and see that it's undervalued and wanting to buy, so they will bid the price up. If the owners are smart they will not sell much if any of their shares and allow the bidders to drive the price up to a point where the longs are willing to begin selling.
You see this occur often when a company announces good news during non-trading hours. When the market opens the stock will gap up, meaning that there is an area of price movement that has occurred where no stock has traded (providing there was no pre-market activity). Those gaps can occur as a result of buyer demand driving the price of the stock up with little to no acutal buying of shares occurring.
Hope that helps.
Rich
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