Prosecution History Disclaimer: Beware of What You Clearly and Unambiguously Say

Patent prosecutors typically are cautious when making arguments that distinguish their client's invention from the prior art. This caution was traditionally based on the concern that later, when the client enforced its patent rights against a potential infringer, these arguments may provide the basis for restricting the range of equivalents available to the patentee under the doctrine of prosecution history estoppel. Prosecution history estoppel normally limits the range of equivalent elements that are available to satisfy a claim element under a doctrine of equivalents analysis (<i>ie</i>, when there is no literal infringement of that claim element). Recent decisions by the Federal Circuit not only reaffirm the significance of statements made during prosecution; they also extend their impact to a literal infringement analysis. A patentee who during prosecution "clearly and unequivocally" disavows the prior art (or even defines the invention) may affect the literal scope of the claims. This doctrine is now regularly referred to as prosecution history disclaimer.

24 minute read May 01, 2004 at 04:38 PM
By
Jonathan S. Caplan and Benu Mehra
Prosecution History Disclaimer: Beware of What You Clearly and Unambiguously Say

Patent prosecutors typically are cautious when making arguments that distinguish their client's invention from the prior art.

This premium content is locked for LawJournalNewsletters subscribers only

ENJOY UNLIMITED ACCESS TO THE SINGLE SOURCE OF OBJECTIVE LEGAL ANALYSIS, PRACTICAL INSIGHTS, AND NEWS IN LawJournalNewsletters

  • Stay current on the latest information, rulings, regulations, and trends
  • Includes practical, must-have information on copyrights, royalties, AI, and more
  • Tap into expert guidance from top entertainment lawyers and experts
Subscribe Now

Already have an account? Sign In Now

For enterprise-wide or corporate access, please contact Customer Service at [email protected] or call 1-877-256-2473.

NOT FOR REPRINT

© 2026 ALM Global, LLC, All Rights Reserved. Request academic re-use from www.copyright.com. All other uses, submit a request to [email protected]. For more information visit Asset & Logo Licensing.

Continue Reading

How Courts Interpret and Apply the Interplay Between the Bankruptcy Code and Medicare Program Act

The combination of increasing operating costs and uncertain government reimbursement funding continues to place health care providers under financial pressure, and in many cases, financial distress. Given the importance of Medicare/Medicaid funding of claims under provider agreements with the federal government, how courts interpret and apply the interplay between the Bankruptcy Code and Medicare Program Act determines the disposition of hundreds of millions of dollars of claims for reimbursement that support the health care system.

April 30, 2026

AI Transparency: Clear Explanations Matter More Than Disclosure

As AI becomes embedded in everyday business and legal operations, organizations are confronting a new expectation: simply disclosing AI use is no longer enough. A critical shift is taking place in the legal industry: transparency is no longer just about disclosure; it’s about comprehension.

April 30, 2026