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In Bilski v. Kappos, the Supreme Court declined calls to categorically exclude business methods—or any technology—from the patent law. It also rejected as the sole test of subject matter eligibility the Federal Circuit’s deeply-flawed machine-or-transformation test, under which no process is patentable unless it is tied to a particular machine or transforms an article to another state or thing. Subsequent developments threaten to undo that holding, however. Relying on the Court’s description of the Federal Circuit test as a “useful and important clue,” the U.S. Patent and Trademark Office, patent litigants, and district courts have all continued to rely on the machine-or-transformation test in the wake of Bilski: no longer as the sole rule, but as a presumptive starting point that threatens to effectively become mandatory. In this Article, we suggest a new way to understand the exclusion of abstract ideas from patentable subject matter. No class of invention is inherently too abstract for patenting. Rather, the rule against patenting abstract ideas is an effort to prevent inventors from claiming their ideas too broadly. By requiring that patent claims be limited to a specific set of practical applications of an idea, the abstract ideas doctrine both makes the scope of the resulting patent clearer and leaves room for subsequent inventors to improve upon—and patent new applications of—the same basic principle. Recasting the abstract ideas doctrine as an overclaiming test eliminates the constraints of the artificial machine-or-transformation test, as well as the pointless effort to fit inventions into permissible or impermissible categories. It also helps understand some otherwise-inexplicable distinctions in the case law. Testing for overclaiming allows courts to focus on what really matters: whether the scope of the patentee’s claims are commensurate with the invention’s practical, real-world contribution. This inquiry, we suggest, is the touchstone of the abstract ideas analysis, and the way out of the post-Bilski confusion.


patents, law, Bilski, invention, MOT, Patentable Subject Matter, 101, Diehr, business methods, Software, Federal Circuit

Publication Title

Stanford Law Review

Publication Citation

63 Stan. L. Rev. 1315 (2011)