Anti Trust is comprised of laws that are regulations that encourage competition by limiting the market power of any particular firm. This often involves ensuring that mergers and acquisitions don’t overly concentrate market power or form monopolies, as well as breaking up firms that have become monopolies.

Antitrust laws also prevent multiple firms from colluding or forming a cartel to limit competition through practices such as price fixing. Due to the complexity of deciding what practices will limit competition, antitrust law has become a distinct legal specialization.