A proposed class of patients accusing Quest Diagnostics of maintaining a lab service monopoly argued on appeal in the 9th Circuit on November 15, 2017 that the district court improperly dismissed its suit, and that under the Supreme Court’s Twombly and Iqbal cases, the court should not act as a gatekeeper for antitrust cases just because they’re costly. The 9th Circuit affirmed the lower court’s judgment, agreeing that plaintiffs failed to state a claim to support their three theories for how Quest monopolized the Northern California medical diagnostic testing market. The original suit filed in Jan 2015 alleged that Quest violated the Sherman Act and California’s Cartwright Act by paying kickbacks, colluding with insurers and acquiring competitors to monopolize the diagnostic service market.