Patent holders can’t necessarily buy off a would-be competitor who is challenging a patent’s validity, a unanimous Supreme Court ruled this morning. The court’s In re Cipro Cases I & II opinion, authored by Justice Kathryn Werdegar, interprets California antitrust law as a 2-year-old U.S. Supreme Court decision construed federal law and concludes, “Some patents are valid; some are not. Sometimes competition would infringe; sometimes it would not. Parties illegally restrain trade when they privately agree to substitute consensual monopoly in place of potential competition that would have followed a finding of invalidity or noninfringement.” Today’s decision reverses the Fourth District, Division One, Court of Appeal.