MARKMAN Et Al. v. WESTVIEW INSTRUMENTS, INC., Et Al.

Background

Markman is an inventor who owned a U.S. patent for an inventory control system used in dry-cleaning stores. He sued Westview, a company that sold a similar keyboard-and-bar‑code system, claiming infringement. At trial, a jury found infringement, but the trial judge later set aside the verdict after concluding the patent’s use of the word “inventory” required tracking physical articles of clothing rather than merely tracking invoices or totals. The Federal Circuit held that judges, not juries, should construe patent claims, and this Court affirmed that allocation of responsibility.

Reasoning

The Court examined whether deciding the meaning of claim language is a jury fact question under the Seventh Amendment’s guarantee of a jury trial or a question of law for judges. Looking at history and precedent, the opinion found no clear 18th‑century practice requiring juries to define patent terms. The opinion reviewed cases such as Winans, Bischoff, and Tucker and explained that earlier decisions and treatises support the judge’s role in construing written instruments. It emphasized practical concerns: patent claims are technical, judges can integrate expert testimony into a document‑wide interpretation, and consistent, uniform treatment across courts is important, so judges are better placed to decide claim meaning.

Real world impact

Patent trials will now have judges, not juries, decide what claim words mean. Experts still testify, but judges weigh that evidence in a legal interpretation. The ruling promotes more consistent outcomes across trials and appeals, affecting inventors, technology companies, and others engaged in patent litigation nationwide.