Opinion of the Court

The Court of Appeals for the Ninth Circuit affirmed the judgment in an unpublished opinion. Judgt. order reported at 907 F. 2d 154 (1990). The court expressly ruled that the trial court had properly instructed the jury on the Sherman Act claims and found that the evidence supported the liability verdicts as well as the damages awards on these claims. The court then affirmed the judgment of the District Court, finding it unnecessary to rule on challenges to other violations found by the jury. App. to Pet. for Cert. A28. On the § 2 issue that petitioners present here, the Court of Appeals, noting that the jury had found that petitioners had violated §2 without specifying whether they had monopolized, attempted to monopolize, or conspired to monopolize, held that the verdict would stand if the evidence supported any one of the three possible violations of § 2. Id., at A15. The court went on to conclude that a case of attempted monopolization had been established. The court rejected petitioners' argument that attempted monopolization had not been established because respondents had failed to prove that petitioners had a specific intent to monopolize a relevant market. The court also held that in order to show that respondents'

4 The District Court's jury instructions were transcribed as follows: "In order to win on the claim of attempted monopoly, the Plaintiff must prove each of the following elements by a preponderance of the evidence: first, that the Defendants had a specific intent to achieve monopoly power in the relevant market; second, that the Defendants engaged in exclusionary or restrictive conduct in furtherance of its specific intent; third, that there was a dangerous probability that Defendants could sooner or later achieve [their] goal of monopoly power in the relevant market; fourth, that the Defendants' conduct occurred in or affected interstate commerce; and, fifth, that the Plaintiff was injured in the business or property by the Defendants' exclusionary or restrictive conduct.

"If the Plaintiff has shown that the Defendant engaged in predatory conduct, you may infer from that evidence the specific intent and the dangerous probability element of the offense without any proof of the relevant market or the Defendants' marketing [sic] power." Id., at 251-252. See also App. to Pet. for Cert. A16, A20.

Opinion of the Court

attempt to monopolize was likely to succeed it was not necessary to present evidence of the relevant market or of the defendants' market power. In so doing, the Ninth Circuit relied on Lessig v. Tidewater Oil Co., 327 F. 2d 459 (CA9), cert. denied, 377 U. S. 993 (1964), and its progeny. App. to Pet. for Cert. A18-A19. The Court of Appeals noted that these cases, in dealing with attempt to monopolize claims, had ruled that "if evidence of unfair or predatory conduct is presented, it may satisfy both the specific intent and dangerous probability elements of the offense, without any proof of relevant market or the defendant's marketpower [sic]." Id., at A19. If, however, there is insufficient evidence of unfair or predatory conduct, there must be a showing of "relevant market or the defendant's marketpower [sic]." Ibid. The court went on to find:

"There is sufficient evidence from which the jury could conclude that the S. I. Group and Spectrum Group engaged in unfair or predatory conduct and thus inferred that they had the specific intent and the dangerous probability of success and, therefore, McQuillan did not have to prove relevant market or the defendant's marketing power." Id., at A21.

The decision below, and the Lessig line of decisions on which it relies, conflicts with holdings of courts in other Circuits. Every other Court of Appeals has indicated that proving an attempt to monopolize requires proof of a dangerous probability of monopolization of a relevant market.5 We

5 See, e. g., CVD, Inc. v. Raytheon Co., 769 F. 2d 842, 851 (CA1 1985), cert. denied, 475 U. S. 1016 (1986); Twin Laboratories, Inc. v. Weider Health & Fitness, 900 F. 2d 566, 570 (CA2 1990); Harold Friedman, Inc. v. Kroger Co., 581 F. 2d 1068, 1079 (CA3 1978); Abcor Corp. v. AM Int'l, Inc., 916 F. 2d 924, 926, 931 (CA4 1990); C. A. T. Industrial Disposal, Inc. v. Browning-Ferris Industries, Inc., 884 F. 2d 209, 210 (CA5 1989); Arthur S. Langenderfer, Inc. v. S. E. Johnson Co., 917 F. 2d 1413, 1431-1432 (CA6 1990), cert. denied, 502 U. S. 899 (1991); Indiana Grocery, Inc. v. Super Valu Stores, Inc., 864 F. 2d 1409, 1413-1416 (CA7 1989); General Indus

Opinion of the Court

granted certiorari, 503 U. S. 958 (1992), to resolve this conflict among the Circuits. We reverse.

6

II

While § 1 of the Sherman Act forbids contracts or conspiracies in restraint of trade or commerce, §2 addresses the actions of single firms that monopolize or attempt to monopolize, as well as conspiracies and combinations to monopolize. Section 2 does not define the elements of the offense of attempted monopolization. Nor is there much guidance to be had in the scant legislative history of that provision, which was added late in the legislative process. See 1 E. Kintner, Legislative History of the Federal Antitrust Laws and Related Statutes 23-25 (1978); 3 P. Areeda & D. Turner, Antitrust Law ¶617, pp. 39-41 (1978). The legislative history does indicate that much of the interpretation of the necessarily broad principles of the Act was to be left for the courts in particular cases. See, e. g., 21 Cong. Rec. 2460 (1890) (statement of Sen. Sherman). See also 1 Kintner, supra, at 19; 3 Areeda & Turner, supra, ¶ 617, at 40.

This Court first addressed the meaning of attempt to monopolize under §2 in Swift & Co. v. United States, 196 U. S. 375 (1905). The Court's opinion, written by Justice Holmes, contained the following passage:

tries Corp. v. Hartz Mountain Corp., 810 F. 2d 795, 804 (CA8 1987); Colorado Interstate Gas Co. v. Natural Gas Pipeline Co. of America, 885 F. 2d 683, 693 (CA10 1989), cert. denied, 498 U. S. 972 (1990); Key Enterprises of Delaware, Inc. v. Venice Hospital, 919 F. 2d 1550, 1565 (CA11 1990); Neumann v. Reinforced Earth Co., 252 U. S. App. D. C. 11, 15-16, 786 F. 2d 424, 428-429, cert. denied, 479 U. S. 851 (1986); Abbott Laboratories v. Brennan, 952 F. 2d 1346, 1354 (CA Fed. 1991), cert. denied, 505 U. S. 1205 (1992).

6 Our grant of certiorari was limited to the first question presented in the petition: "Whether a manufacturer's distributor expressly absolved of violating Section 1 of the Sherman Act can, without any evidence of market power or specific intent, be found liable for attempting to monopolize solely by virtue of a unique Ninth Circuit rule?" Pet. for Cert. i.

Opinion of the Court

"Where acts are not sufficient in themselves to produce a result which the law seeks to prevent-for instance, the monopoly-but require further acts in addition to the mere forces of nature to bring that result to pass, an intent to bring it to pass is necessary in order to produce a dangerous probability that it will happen. Commonwealth v. Peaslee, 177 Massachusetts 267, 272 [59 N. E. 55, 56 (1901)]. But when that intent and the consequent dangerous probability exist, this statute, like many others and like the common law in some cases, directs itself against that dangerous probability as well as against the completed result." Id., at 396.

The Court went on to explain, however, that not every act done with intent to produce an unlawful result constitutes an attempt. "It is a question of proximity and degree." Id., at 402. Swift thus indicated that intent is necessary, but alone is not sufficient, to establish the dangerous probability of success that is the object of § 2's prohibition of attempts."

The Court's decisions since Swift have reflected the view that the plaintiff charging attempted monopolization must prove a dangerous probability of actual monopolization, which has generally required a definition of the relevant market and examination of market power. In Walker Process Equipment, Inc. v. Food Machinery & Chemical Corp., 382 U. S. 172, 177 (1965), we found that enforcement of a fraudulently obtained patent claim could violate the Sherman Act. We stated that, to establish monopolization or attempt to monopolize under §2 of the Sherman Act, it would

"Justice Holmes confirmed that this was his interpretation of Swift in Hyde v. United States, 225 U. S. 347 (1912). In dissenting in that case on other grounds, the Justice, citing Swift, stated that an attempt may be found where the danger of harm is very great; however, "combination, intention and overt act may all be present without amounting to a criminal attempt.... There must be dangerous proximity to success. 225 U. S.,

at 387-388.

Opinion of the Court

be necessary to appraise the exclusionary power of the illegal patent claim in terms of the relevant market for the product involved. Ibid. The reason was that "[w]ithout a definition of that market there is no way to measure [the defendant's] ability to lessen or destroy competition." Ibid.

Similarly, this Court reaffirmed in Copperweld Corp. v. Independence Tube Corp., 467 U. S. 752 (1984), that "Congress authorized Sherman Act scrutiny of single firms only when they pose a danger of monopolization. Judging unilateral conduct in this manner reduces the risk that the antitrust laws will dampen the competitive zeal of a single aggressive entrepreneur." Id., at 768. Thus, the conduct of a single firm, governed by §2, "is unlawful only when it threatens actual monopolization." Id., at 767. See also Lorain Journal Co. v. United States, 342 U. S. 143, 154 (1951); United States v. Griffith, 334 U. S. 100, 105-106 (1948); American Tobacco Co. v. United States, 328 U. S. 781, 785 (1946).

The Courts of Appeals other than the Ninth Circuit have followed this approach. Consistent with our cases, it is generally required that to demonstrate attempted monopolization a plaintiff must prove (1) that the defendant has engaged in predatory or anticompetitive conduct with (2) a specific intent to monopolize and (3) a dangerous probability of achieving monopoly power. See 3 Areeda & Turner, supra, ¶820, at 312. In order to determine whether there is a dangerous probability of monopolization, courts have found it necessary to consider the relevant market and the defendant's ability to lessen or destroy competition in that market.8

8 See, e. g., Arthur S. Langenderfer, Inc. v. S. E. Johnson Co., 917 F. 2d, at 1431-1432; Twin Laboratories, Inc. v. Weider Health & Fitness, 900 F. 2d, at 570; Colorado Interstate Gas Co. v. Natural Gas Pipeline Co. of America, 885 F. 2d, at 693; Indiana Grocery, Inc. v. Super Valu Stores, Inc., 864 F.2d, at 1413-1416; General Industries Corp. v. Hartz Mountain Corp., 810 F. 2d, at 804.