Actions contrary to self-interest, phenomena explained only as the result of concerted action, evidence that defendants created opportunity for regular communication, industry performance data that suggest successful coordination (high profits), absence of legit business rationale for conduct.
(1) Indications of express collusion: extraordinary coincidence (e.g. Interstate), simultaneous change of conduct, evidence of communications (opportunity for regular communication);
(2) Motivation: but presence of motive for common action is yet not enough;
(3) Acts against self-interest: can each firm's behavior be independently explained? Contrary to self-interests unless pursued as part of collective plan? To be conspirational, you need both a motive and some reason why. Act contrary to self-interest of the actor is evidence of conspiracy.
· Self-interest unrelated to rivals' behavior
· Self-interest that depends on rivals' behavior acts contrary to self-interest unless undertaken by all the firms... rule out independent behavior. Indicate interdependence, but doesn't indicate what sorts of interactions there are among the firms
(4) Phenomena that can be explained rationally only as a result of a concert of action;
(5) Absence of plausible legitimate business rationale... suspicious conduct; or presentation of contrived rationales for certain conduct;
(6) Performance data (e.g. extraordinary prices or profits, increased prices when demand declines) à suggest successful coordination. Yet, hard to find this data