Matsushita (Ds) are 21 corporations that manufacture or sell 'consumer electronic products (CEP).' The 21 firms include both Japanese manufacturers of CEPs and American firms, controlled by Japanese parents, that sell the Japanese-manufactured products. Zenith Radio Corporation (P) is an American firm that manufactures and sells television sets. National Union Electric Corporation (P) is the corporate successor to Emerson Radio Company, an American firm that manufactured and sold television sets until 1970, when it withdrew from the market after sustaining substantial losses. Ps began this lawsuit in 1974, claiming that Ds had illegally conspired to drive American firms from the American CEP market. The conspiracy was a '`scheme to raise, fix and maintain artificially high prices for television receivers sold in Japan and, at the same time, to fix and maintain low prices for television receivers exported to and sold in the United States. These 'low prices' were allegedly at levels that produced substantial losses for Ds. The conspiracy began as early as 1953, and according to Ps was in full operation by sometime in the late 1960's. Ps claimed that various portions of this scheme violated §§ 1 and 2 of the Sherman Act, § 2(a) of the Robinson-Patman Act, § 73 of the Wilson Tariff Act, and the Antidumping Act of 1916. After several years of discovery, Ds filed motions for summary judgment on all claims against them. The District Court found the bulk of the evidence on which Ps relied inadmissible. In an opinion spanning 217 pages, the court found that the admissible evidence did not raise a genuine issue of material fact as to the existence of the alleged conspiracy. Ps' claims rested on the inferences that could be drawn from petitioners' parallel conduct in the Japanese and American markets, and from the effects of that conduct on petitioners' American competitors. The court found that any inference of conspiracy was unreasonable, because (i) some portions of the evidence suggested that petitioners conspired in ways that did not injure respondents, and (ii) the evidence that bore directly on the alleged price-cutting conspiracy did not rebut the more plausible inference that Ds were cutting prices to compete in the American market and not to monopolize it. Summary judgment therefore was granted to Ds. The Court of Appeals for the Third Circuit reversed. It determined that much of the evidence excluded by the District Court was in fact admissible. The court acknowledged that 'there are legal limitations upon the inferences which may be drawn from circumstantial evidence,' but it found that 'the legal problem . . . is different' when 'there is direct evidence of concert of action.' The court reasoned, cases concerning the limitations on inferring conspiracy from ambiguous evidence were not dispositive. Turning to the evidence, the court determined that a factfinder reasonably could draw the following conclusions: 1. The Japanese market for CEPs was characterized by oligopolistic behavior, with a small number of producers meeting regularly and exchanging information on price and other matters. This created the opportunity for a stable combination to raise both prices and profits in Japan. American firms could not attack such a combination because the Japanese Government imposed significant barriers to entry. 2. Petitioners had relatively higher fixed costs than their American counterparts, and therefore needed to operate at something approaching full capacity in order to make a profit. 3. Petitioners' plant capacity exceeded the needs of the Japanese market. 4. By formal agreements arranged in cooperation with Japan's Ministry of International Trade and Industry (MITI), petitioners fixed minimum prices for CEPs exported to the American market. The parties refer to these prices as the 'check prices,' and to the agreements that require them as the 'check price agreements.' 5. Petitioners agreed to distribute their products in the United States according to a 'five company rule': each Japanese producer was permitted to sell only to five American distributors. 6. Petitioners undercut their own check prices by a variety of rebate schemes. Id., at 311. Petitioners sought to conceal these rebate schemes both from the United States Customs Service and from MITI, the former to avoid various customs regulations as well as action under the antidumping laws, and the latter to cover up petitioners' violations of the check-price agreements. The Court of Appeals concluded that a reasonable factfinder could find a conspiracy to depress prices in the American market in order to drive out American competitors, which conspiracy was funded by excess profits obtained in the Japanese market. The court apparently did not consider whether it was as plausible to conclude that petitioners' price-cutting behavior was independent and not conspiratorial. The court then addressed Ds' claim that they could not be held liable under the antitrust laws for conduct that was compelled by a foreign sovereign. Because MITI required Ds to enter into the check-price agreements, liability could not be premised on those agreements. The court concluded that this case did not present any issue of sovereign compulsion, because the check-price agreements were being used as 'evidence of a low export price conspiracy' and not as an independent basis for finding antitrust liability. The Supreme Court granted certiorari to determine (i) whether the Court of Appeals applied the proper standards in evaluating the District Court's decision to grant petitioners' motion for summary judgment, and (ii) whether petitioners could be held liable under the antitrust laws for a conspiracy in part compelled by a foreign sovereign.