Because Socony makes questions of power and success irrelevant under Section 1, given proof of a conspiracy, the concept of attempt comes into play only under Section 2. An attempt to monopolize is a distinct violation of the Sherman Act, and has a distinct set of doctrines.

The key difference between an attempt and a monopolization charge is that in the former, the defendant either did not succeed or the Court does not find significant evidence of success. Consider, for example, the monopolization charge in Griffith. The defendant in Griffith had not achieved monopoly status. However, the government charged the defendant with monopolization because of the evidence of success: the percentage of towns in which the Griffith circuit enjoyed a local monopoly had increased roughly 50 to 60 percent over the period in which the defendants had adopted their practice of block-purchasing films. Had there been no such evidence of success, the appropriate charge would have been attempt to monopolize.

THE SWIFT FORMULA AND MODERN DOCTRINE

The doctrinal formula applied in the area of attempts comes from Justice Holmes's opinion in Swift & Co. v. United States. Justice Holmes described an attempt as conduct that closely approaches but does not quite attain complete monopolization plus a wrongful intent to monopolize. Thus, attempt requires proof of specific intent plus a dangerous probability of success. The cases below put flesh on this skeletal formula.