Diamond v. Diehr
450 U.S. 175 (1981)

  • Diehr and Lutton came up with a math equation to determine how long to cure rubber. They developed a computer program that they installed on a rubber molding press so that it could better make precision molded rubber products.
    • Basically, Diehr and Lutton came up with an equation for how long to cure the rubber to get various characteristics, and then wrote a computer program where you type in what you want and it calculates how long the curing process should be. Like a toaster oven, at the right time, the door to the molding press pops open and the piece is ready.
  • Diehr and Lutton applied for a patent on their process for curing rubber. The USPTO denied the patent. Diehr and Lutton appealed.
    • The USPTO found that the process was unpatentable subject matter under 35 U.S.C. 101.
    • The USPTO found that the steps performed by the computer were unpatentable as a computer program under Gottschalk v. Benson (409 U.S. 63 (1972)).
  • The Court of Customs and Patent Appeals reversed. The USPTO appealed.
    • The Court of Customs and Appealed found that at an otherwise patentable invention did not become unpatentable simply because a computer was involved.
  • The US Supreme Court affirmed and granted the patent.
    • The US Supreme Court found that the execution of a physical process, controlled by running a computer program was patentable.
    • The Court noted that software algorithms could not be patented. However, the Court found that the mere presence of a software element did not make an otherwise patent-eligible machine or process un-patentable.
      • The Court found that under 101, the invention must be considered "as a whole." In this case the invention was comprised not just of a software algorithm, but also some physical items like a molding press. It also results in a specific, quantifiable result (cured rubber).
      • The Court found that 101 should be read as broadly as possible.
  • Truthfully, Diehr's invention was mostly just a math equation. The physical parts consisted of a thermometer and spring-loaded door. Thermometers, spring-loaded doors, and rubber molding presses were all known processes. The only novel part of Diehr's invention was the math equation.
    • Gottschalk found that math equations were not patentable. How is this case distinguishable?
      • Gottschalk's computer program was just a program, he didn't specify a use for it. Diehr was only making a claim for making rubber. Does the fact that the math is connected to the machinery make the difference?
    • The Court specifically rejected the idea of breaking down an invention into component parts and subjecting each part to a novelty and statutory subject matter review.
      • See Parker v. Flook (437 U.S. 584 (1978)).