Great Atlantic and Pacific Tea Co. v. Supermarket Equipment Corp.
In Great Atlantic & Pacific Tea Co. v. Supermarket Equipment Corp., 340 U.S. 147 (1950), the U.S. Supreme Court established a presumption against granting a patent based on the combination of elements found in the prior art.
The Court held that a "patent for a combination which only unites old elements with no change in their respective functions ... obviously withdraws what is already known into the field of its monopoly and diminishes the resources available to skillful men." Id. at 152.
Justice Hugo Black was generally opposed to upholding almost any patent. He joined a concurrence by Justice William O. Douglas that listed numerous examples of obvious "inventions" that had improperly become patented.