Brandeis is back, with today’s neo-Brandeisians reflexively opposing virtually all mergers involving large firms. For them, industry concentration has grown to crisis proportions and breaking up big companies should be the animating goal not just of antitrust policy but of U.S. economic policy generally. The key to understanding the neo-Brandeisian opposition to the Whole Foods/Amazon mergers is that it has nothing to do with consumer welfare, and everything to do with a large firm animus. Sabeel Rahman, a Roosevelt Institute scholar, concedes that big firms give us higher productivity, and hence lower prices, but he dismisses the value of that. He writes, “If consumer prices are our only concern, it is hard to see how Amazon, Comcast, and companies such as Uber need regulation.” And this gets to the key point regarding most of the opposition to the merger: it had nothing to do with concerns about monopolistic effects on economic efficiency or consumer prices. It had everything to do with opposition to big firm for the sole reason that they are big.