Also known as the HSR Act and Hart-Scott-Rodino. A federal law requiring parties to certain proposed transactions (such as mergers and acquisitions) to file a notification with the Federal Trade Commission (FTC) and the Department of Justice (DOJ) Antitrust Division. These parties must wait a specified time period before consummating the proposed transaction. During the waiting period, regulators may request additional information or time to review the transaction in order to determine if the transaction is in violation of the federal antitrust laws. (15 U.S.C. § 18a.)