A company can issue more than one type of share, each with its own rights. Common examples are common stock and preferred stock. Preferred shares often come with priority in a sale or liquidation, and are typical in venture financing. Common stock is split into classes as well, often called Class A and Class B, which can differ in voting rights even if they share equally in profits.
A company with dual-class or multi-class shares might give founders or insiders shares carrying ten votes each, while the public receives shares with one vote. Classes may be convertible into one another, and some structures include sunset provisions, which end the extra voting rights after a period or an event.
The rights are set out in the company charter, and they can change who controls decisions, regardless of how many shares each person owns.
Read the description of capital stock in the prospectus, and check the votes per share for each class, the conversion terms and any sunset clause.