Software-related inventions have had an uneasy relationship with the patent-eligible subject matter requirement of Section 101 of the Patent Act. In applying the requirement, the Supreme Court has historically characterized mathematical algorithms and formulas simpliciter as sufficiently analogous to laws of nature to warrant judicial exclusion as abstract ideas. The Court has also found “the mere recitation of a generic computer” in a patent claim as tantamount to “adding the words ‘apply it with a computer,’” a mere drafting effort that does not relieve “the pre-emption concern that undergirds our § 101 jurisprudence.” Lower courts, patent counsel, and commentators have struggled to apply these broad principles to specific software-related inventions, a difficulty largely rooted in the many forms and levels of abstraction in which mathematical algorithms can be situated, both in the computing context and in the terms of a patent claim. Consequently, widely varying approaches to claiming inventions that involve algorithms in their use have perennially complicated efforts to develop a coherent doctrine of unpatentable abstract ideas.