Logourl black
From our private database of 14,200+ case briefs...

Graver Tank v. Linde Air Products Co.

United States Supreme Court
339 U.S. 605 (1950)


Facts

Linde Air Products Co. (Linde) (plaintiff) owned a patent for Unionmelt Grade 20, a flux composition used in welding. Though the patent claimed alkaline earth metal silicate and calcium fluoride as ingredients, Unionmelt actually contained calcium and magnesium silicates. Linde sued Graver Tank & Manufacturing Co. (Graver) (defendant), claiming Graver’s flux composition, Lincolnweld 660, infringed the patent. Though the uses and welding quality produced by the compositions were largely the same, Lincolnweld did not contain magnesium like Unionmelt. Instead, Lincolnweld contained manganese, which is not an alkaline earth metal. At trial, chemists skilled in the art testified that manganese and magnesium act similarly in chemical reactions, and that, for purposes of the patent, manganese could be considered an alkaline earth metal. Additionally, evidence established that prior art taught the substitution of manganese silicate in welding fluxes. Graver produced no evidence demonstrating that Lincolnweld was discovered or developed based on independent research or experimentation. The trial court concluded that Lincolnweld and Unionmelt were substantially the same in use and quality of results, and that Lincolnweld was equivalent to Unionmelt for purposes of metal welding. Thus, the trial court held that the patent claims were infringed. On appeal before the United States Supreme Court, the Court considered the applicability of the doctrine of equivalents to the flux claims.

Rule of Law

Issue

Holding and Reasoning (Jackson, J.)

Dissent (Black, J.)

Dissent (Douglas, J.)

What to do next…

  1. Unlock this case brief with a free (no-commitment) trial membership of Quimbee.

    You’ll be in good company: Quimbee is one of the most widely used and trusted sites for law students, serving more than 97,000 law students since 2011. Some law schools—such as Yale, Vanderbilt, Berkeley, and the University of Illinois—even subscribe directly to Quimbee for all their law students. Read our student testimonials.

  2. Learn more about Quimbee’s unique (and proven) approach to achieving great grades at law school.

    Quimbee is a company hell-bent on one thing: helping you get an “A” in every course you take in law school, so you can graduate at the top of your class and get a high-paying law job. We’re not just a study aid for law students; we’re the study aid for law students. Read more about Quimbee.

Here's why 240,000 law students have relied on our case briefs:

  • Written by law professors and practitioners, not other law students. 14,200 briefs, keyed to 189 casebooks. Top-notch customer support.
  • The right amount of information, includes the facts, issues, rule of law, holding and reasoning, and any concurrences and dissents.
  • Access in your classes, works on your mobile and tablet. Massive library of related video lessons and high quality multiple-choice questions.
  • Easy to use, uniform format for every case brief. Written in plain English, not in legalese. Our briefs summarize and simplify; they don’t just repeat the court’s language.