## Facts

- Cigarette wholesalers, on behalf of a certified class, sued major tobacco manufacturers alleging a 1993–2000 agreement to fix cigarette prices in violation of Sherman Act § 1 and seeking damages and injunctive relief under the Clayton Act.
- The market was highly concentrated; the principal manufacturers produced nearly all cigarettes sold in the United States, making the industry an oligopoly.
- After “Marlboro Friday” in April 1993, price competition intensified; later, the manufacturers implemented a series of roughly parallel list-price increases between 1993 and 2000.
- Plaintiffs claimed the near-simultaneous, uniform price increases and related industry behavior reflected a continuing price-fixing conspiracy causing substantial wholesale overcharges.
- Defendants contended the pricing pattern was consistent with lawful interdependent conduct typical of oligopolies and rational unilateral responses to market conditions.
- The district court entered final summary judgment for defendants, concluding plaintiffs proved, at most, conscious parallelism and failed to supply sufficient “plus factors”; it also excluded portions of plaintiffs’ expert testimony.

## Issues

1. Whether plaintiffs produced evidence, including adequate “plus factors,” that tended to exclude independent action and permitted a reasonable inference of an agreement to fix prices under Sherman Act § 1.
2. Whether summary judgment was improper because the district court allegedly weighed evidence or drew inferences against the nonmoving party.
3. Whether exclusion and discounting of plaintiffs’ expert testimony was erroneous and, if admitted, would have created a triable issue of conspiracy.

## Decision

- The Eleventh Circuit affirmed final summary judgment for all defendants.
- The court held parallel pricing in an oligopoly, without more, is insufficient to prove a Sherman Act § 1 agreement.
- The court concluded plaintiffs’ circumstantial “plus factor” evidence (signaling/announcements, purported conduct against self-interest, and monitoring/information awareness) did not sufficiently exclude independent, interdependent action.
- The court determined defendants’ economic explanations showed the challenged conduct was plausibly rational without an agreement, defeating an inference of conspiracy at summary judgment.
- The court upheld exclusion/limited weight of plaintiffs’ expert evidence because it did not reliably distinguish lawful oligopoly interdependence from collusion and therefore did not create a genuine dispute of material fact.

## Legal Principles

- To prove a Sherman Act § 1 conspiracy based on circumstantial evidence in an oligopoly, a plaintiff must offer evidence that tends to exclude the possibility of independent action and supports an inference of a meeting of the minds.
- Conscious parallelism—lawful interdependent pricing behavior common in concentrated markets—does not, by itself, establish an unlawful agreement.
- “Plus factors” must meaningfully tip the evidentiary balance toward conspiracy; ambiguous evidence equally consistent with lawful conduct does not defeat summary judgment.
- Public announcements, trade-press communications, and vigilant monitoring of competitors may be ordinary business behavior in oligopolies and are not inherently probative of agreement without additional indicia of coordination.
- Expert economic testimony must do more than label outcomes “consistent with collusion”; it must reliably separate collusion from lawful interdependent conduct to support an inference that excludes independent action.

## Conclusion

The court held that the wholesalers’ proof showed only parallel pricing in an oligopoly and did not provide sufficiently probative plus factors or expert analysis to exclude lawful independent, interdependent conduct; summary judgment for the manufacturers was therefore proper.


Williamson Oil Co. v. Philip Morris USA, 346 F.3d 1287 (11th Cir. 2003)