Bigelow (Ps) were the owners in partnership of the Jackson Park Theatre, located on the south side of Chicago. RKO Radio Pictures, Inc., Loew's, Inc., Twentieth Century-Fox Film Corporation, Paramount Pictures, Inc., and Vitagraph, Inc ., (Ds) are distributors of motion picture films. RKO also owns two large first-run theatres in the Chicago Loop. Respondent Balaban & Katz Corporation is a motion picture exhibitor, which operates a chain of some fifty theatres in Chicago and its suburbs, including the Maryland Theatre and others on the south side of Chicago which compete with the petitioners' Jackson Park Theatre. Balaban & Katz is a subsidiary of Paramount. Respondent Warner Bros. Circuit Management Corporation is an exhibitor which operates more than twenty theatres in Chicago, including several on Chicago's south side which also compete with petitioners' theatre. Warner Bros. Circuit Management Corporation and Vitagraph are subsidiaries of Warner Bros. Pictures, Inc. Respondent Warner Bros. Theatres, Inc., is also affiliated with Warner Bros. Pictures, Inc. and holds title to certain of the Warner theatres. Bigelow (P) sued Ds in the District Court for Northern Illinois under 1, 2 and 7 of the Sherman Act, 26 Stat. 209, and 4 and 16 of the Clayton Act, 38 Stat. 731, 15 U.S.C. 1, 2, 15, and 26, 15 U.S.C.A. 1, 2, 15, 26, for an injunction and to recover treble damages. P owned the Jackson Park motion picture theatre in Chicago. P claims that Ds, some of whom are distributors of moving picture films, and some of whom own or control moving picture theatres in Chicago, entered into a conspiracy to which film was distributed among moving picture theatres in the Chicago district in such a manner that theatres owned by some of the conspirators were enabled to secure and show feature pictures in advance of independent exhibitors, not affiliated with D. P claims that it was prevented from securing pictures for exhibition in their theatre until after the preferred exhibitors had been able to show them in the earlier and more desirable runs, and that P has been discriminated against in the distribution of feature films in favor of competing theatres owned or controlled by some of the Ds. Ps charged that in consequence they had been subjected to loss of earnings in excess of $120,000 during the five year period from July 27, 1937, to July 27, 1942. The matter of the injunction was reserved, and the case went to trial solely on the question of damages. The jury returned a verdict for $120,000 in P’s favor. The trial court gave judgment for treble that amount, as prescribed by 4 of the Clayton Act. To establish damages P used a comparison of receipts between theaters that were part of the conspiracy with one that wasn't. This evidence showed that during the five year period, the innocent theatre net receipts after deducting film rentals paid to distributors exceeded the non-innocent theater's like receipts by $115,982.34. P also showed its receipts from the operation of the Jackson Park Theatre less cost of film for the five year period following July 1937, with the corresponding receipts for the four years immediately preceding, after making an allowance for the elimination of 'Bank Night' receipts. The comparison shows a falling off of Ps' receipts during the five year period aggregating $125,659.00, which was more than $5,000 in excess of the $120,000 damage demanded by Ps' complaint. Despite the conspiracy and with the advent of double features, Ps' theater was able to obtain first-run films. The trial court left it to the jury to say whether double featuring was introduced as a part of a conspiracy among respondents, or as a spontaneous manifestation in the industry. Assuming the latter, we agree with the Circuit Court of Appeals, which, in sustaining the jury's finding of an unlawful conspiracy to maintain the described system of distribution, held that when the double featuring was established, all film which had not already been shown 'was taken away by Ds' prior contracts, made pursuant to and a part of the conspiracy, and placed under the restriction of the illegal system, and thereafter was not obtainable by Ps, except by use of the illegal system.' The Circuit Court of Appeals for the Seventh Circuit reversed on the sole ground that the evidence of damage was not sufficient for submission to the jury, and directed the entry of a judgment for respondents non obstante veredicto. The court granted certiorari.