By Jon Dubrow (July 17, 2018, 3:24 PM EDT) -- As the world knows, U.S. District Judge Richard Leon delivered a resounding win for AT&T / Time Warner in June in the first vertical merger injunction proceeding in roughly 40 years. While only one judge's opinion, and the U.S. Department of Justice is appealing the decision, it is significant because the government brings so few vertical cases. This case made brutally clear how hard it is for the government to win a merger case without a presumption of a substantial lessening of competition under United States v. Philadelphia Nat'l Bank.[1] While Judge Leon took care to make his opinion narrow, the nature of his evaluation of the government's evidence, to see if it actually supported the economic model the government offered to prove anticompetitive impacts, may reverberate in situations involving competitive theories beyond vertical mergers. One example is the antitrust assessment of acquisitions of a noncontrolling partial interest in a rival. Thus, this narrow opinion may have broader impacts....