George Alexander Mills and Houdry Process Corp. v. Robert C. Watson, Commissioner of Patents

This is a patent case under Rev.Stat. § 4915 (1875). 1 The District Court denied relief, and this appeal followed.

Plaintiffs-appellants say that their invention lies “in the discovery of a particular and unique kaolin clay,” which proved unusually successful as a catalyst in the so-called “catalytic cracking process” for making gasoline. But it is clear that the clay in question — described as “Eureka halloysite” 2 — was already known and available for purchase in the market. What was discovered was that this clay had certain desirable properties not previously realized. The question is…