How Can I Tell If the Float Is Locked Up on a Stock?
" The float value can change if the company decides to repurchase shares from the market or sell more of its authorized shares internally instead of publicly. For example, if a company has a total of 4 million shares and restricts 1 million for the company, the float is 3 million. A stock with a smaller float is more likely to feel the impact of volume spikes and dips".