Despite the promise of efficiency through the use of expert agency adjudication in U.S. patent law, administrative substitution continues to fall short. In a variety of ways, the decade-old system of Patent Office adjudication is simply an additional place to litigate rather than the robust technocratic alternative it was meant to be. These problems have arisen from important defects in the statutory design, but also from the enormous expansion and ascendancy of the Patent Office itself. Moreover, while duplicative litigation over patent validity is recognized and criticized, its scale and scope has eluded detailed empirical analysis until now. This Article documents and measures those ill effects and explains their structural origins. It e...