In City of San Jose v. Office of the Commissioner of Baseball, ___ F.3d ___ (9th Cir. Jan. 15, 2015), the Ninth Circuit affirmed the district court's dismissal of state and federal antitrust claims under the baseball exemption, which Judge Kozinski described as "one of federal law's most enduring anomalies." Slip op. at 3.
The opinion disposed of the UCL claim as well, in this passage:
San Jose also alleges a violation of California’s unfair competition law (UCL). However, under California law, “[i]f the same conduct is alleged to be both an antitrust violation and an ‘unfair’ business act or practice for the same reason—because it unreasonably restrains competition and harms consumers—the determination that the conduct is not an unreasonable restraint of trade necessarily implies that the conduct is not ‘unfair’ toward consumers.” Chavez v. Whirlpool Corp., 113 Cal. Rptr. 2d 175, 184 (Ct. App. 2001). An independent claim under California’s UCL is therefore barred so long as MLB’s activities are lawful under the antitrust laws.
Id. at 11.
I've explained before that Chavez is inconsistent with Cel-Tech on this point. The issue may be resolved by the California Supreme Court in the Cipro matter, which is fully briefed and awaiting oral argument. In re Cipro Cases I & II, No. S198616. My amicus brief for CAOC in Cipro discusses the issue.