In In re Baby Food Antitrust Litigation, 166 F.3d 112 (3d Cir. 1999), the plaintiffs were trying to prove a horizontal conspiracy among Gerber, Heinz, and Beech-Nut. To begin with, there were no direct evidence that these three manufacturers of baby food expressly agreed to fix prices or divide markets in violation of section 1 of the Sherman Act. Then, circumstantial evidences exist for conscious parallelism -- ostensibly independent firms consistently set prices at the same level and update prices at the same time. The class of store owners introduced evidence of e-mails indicating occasional price information exchange or advance notice among sales representatives employed by the three companies. However, conscious parallelism is insufficient