Abstract: Incontestability is a nearly unique feature of American trademark law, with a unique American implementation. The concept of incontestability allows a trademark registrant to overcome arguments that a symbol is merely descriptive of features or qualities of the registrant’s goods or services—for example, “Juicy” for apples. Incontestability provides a nearly irrebuttable presumption of trademark meaning, which is a powerful tool for trademark owners. Unfortunately, incontestability is not granted as carefully as its power would counsel. Courts may misunderstand either the prerequisites for, or the meaning of incontestability, allowing trademark claimants to assert rights that they don’t actually have. Incontestability needs clearer signals about what it is and when it is available. In the absence of serious substantive examination of incontestability at the PTO—which seems unlikely to materialize any time soon—changes designed to increase the salience of incontestability’s requirements to filers and to courts could provide some protection against wrongful assertions. Incontestability can only serve the trademark system if it is granted properly and consistently.