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file-wrapper estoppel

Definitions from Case Law · United States Supreme Court

Definitions from Case Law

From 315 U.S. 126 - Exhibit Supply Co. v. Ace Patents Corp. · 1942Most cited · 656 citing opinions

recourse may not be had to that doctrine [of equivalents] to recapture claims which the patentee has surrendered by amendment

How the Supreme Court has restated “file-wrapper estoppel”

190719101920193019401942 most cited: 315 U.S. 126 - Exhibit Supply Co. v. Ace Patents Corp. (1942)
first stateddeparted

Each Supreme Court definition of “file-wrapper estoppel,” sized by how often later courts cited it. “Change” is measured by wording overlap with earlier definitions — a rough signal, not a semantic judgment.

How often courts cite the cases defining “file-wrapper estoppel”

1900192519501975200020252030245

Court decisions citing the 3 opinions that defined “file-wrapper estoppel” — 1,431 in all, by decade. Counts are citations to the defining cases as a whole, not verified uses of the term. The dip in the most recent years is a data-coverage gap, not a real trend — our corpus holds fewer opinions from the latest years.

All 3 definitions, chronological · 1907–1942

  1. Where an inventor, seeking a broad claim which is rejected, in which rejection he acquiesces, substitutes therefor a narrower claim, he cannot be heard to insist that the construction of the claim allowed shall cover that which has been previously rejected.

  2. It is well settled that where an applicant for a patent to cover a new combination is compelled by the rejection of his application by the Patent Office to narrow his claim by the introduction of a new element, he cannot after the issue of the patent broaden his claim by dropping the element which he was compelled to include in order to secure his patent. The patentee is thereafter estopped to claim the benefit of his rejected claim or such a construction of his amended claim as would be equivalent thereto.