file wrapper estoppel
- A term used in patent law that restricts an applicant from claiming that a more narrowly defined claim aligns with a previously rejected, broader claim. This rule, sometimes referred to as prosecution history estoppel, prevents the manipulation of patent claims
- Due to the principle of file wrapper estoppel, the inventor could not argue that his refined claim was identical to the previously dismissed, broader claim.
- File wrapper estoppel was invoked to prevent the patentee from expanding the scope of his accepted claim to match a previously discarded generalized one.
- The patent office applied file wrapper estoppel, inhibiting the applicant from equating the narrowed claim with the earlier repudiated expansive one.