Courts, the Patent Office, and commentators are in vigorous disagreement about what types of innovation should be patentable, and what, if any, innovation should remain off limits to patenting. This Article shows that the disarray in the area of patentable subject matter results from a widespread failure to take the utilitarian policy underlying patent law seriously. Despite near-universal agreement that patent rights exist to provide incentives for innovation by allowing inventors to recoup their costs of research and development, courts have expanded patentable subject matter to many new fields without first demanding evidence that the newly patentable fields suffer from lack of incentives to innovate. The failure to ask the threshold que...