The Federal Trade Commission is an independent federal agency established by Congress. The FTC is led by five appointed commissioners, and is separated into two different bureaus: the bureau of consumer protection, which focuses on consumer fraud and false advertising, and the bureau of competition, which deals with antitrust matters.
The FTC, being an administrative agency, can take two courses of action against a party possibly violating antitrust laws. First, it can pursue an internal administrative action, bringing the claim against the violating party before an administrative law judge, whose decision will be reviewed by the 5 commissioners. In addition to this, the FTC can file a federal court action in order to obtain an preliminary injunction to block the potential antitrust violation, such as a merger, while the FTC reviews the potential violation through its internal administrative action.