15 U.S.C. § 47

In any suit in equity brought by or under the direction of the Attorney General as provided in the antitrust Acts, the court may, upon the conclusion of the testimony therein, if it shall be then of opinion that the complainant is entitled to relief, refer said suit to the Commission, as a master in chancery, to ascertain and report an appropriate form of decree therein. The Commission shall proceed upon such notice to the parties and under such rules of procedure as the court may prescribe, and upon the coming in of such report such exceptions may be filed and such proceedings had in relation thereto as upon the report of a master in other equity causes, but the court may adopt or reject such report, in whole or in part, and enter such decree as the nature of the case may in its judgment require.