This Article opens a new area of study at the intersection of federalism and privatization. The Supremacy Clause was designed to resolve inevitable conflicts between two sovereign powers. It was not designed for the triangulated clashes amassing in our privatized era—between states and private actors doing federal work. Nonetheless, in scattered and undertheorized precedents, the Supreme Court has held that federal contracts can preempt state law, and that federal contractors can enjoy constitutional immunity from state law. This Article contextualizes these doctrines of “Supremacy, Inc.,” debunks their enabling myths, and argues to overrule them on constitutional and normative grounds.