安信国际在《港股公众持股比例的分析》一文中对香港联交对上市公司的最低公众持股要求有详细解释。另可见《指定的最低公眾持股量及其他上市》。通俗的说，就是普通股民持股比例不能低于25%。
此处公众持股对应的英文为 Public Float，解释如下：
The public float or simply the "float" of a public company is the number of outstanding shares in the hands of public investors as opposed to company officers, directors, or controlling-interest investors. These are the shares that are available for trading.