Prosecution Disclaimer Extends to Inter Partes Reviews

By: Califf Cooper

In Aylus Networks, Inc. v. Apple Inc., (Fed. Cir. May 11, 2017), the Federal Circuit confirmed that a patent owner’s statements made during an inter partes review (“IPR”) can be used to argue prosecution disclaimer.  This means that patent owners enforcing their patents must be even more aware of how their statements during an IPR can affect the scope of their claims and their litigation position.

Prosecution disclaimer prevents patent owners from seeking claim construction positions that recapture specific meanings that were disclaimed during prosecution, and now during IPR.  The disavowing statements must be both clear and unmistakable.  “Thus, when the patentee unequivocally and unambiguously disavows a certain meaning to obtain a patent, the doctrine of prosecution history disclaimer narrows the meaning of the claim consistent with the scope of the claim surrendered.”  Prosecution disclaimer makes sure that claims are not construed one way in order to obtain their allowance or get around prior art in an IPR and then in a different way against accused infringers.  In an IPR, prosecution disclaimer applies to statements made in a preliminary response before an institution decision as well as to statements made after institution.

In Aylus, the patent owner made statements in a preliminary response during an IPR proceeding regarding how the invention worked to reduce bandwidth which was a key aspect of the invention.  The Federal Circuit found prosecution disclaimer applied where Aylus stated that certain claims “require that…only the control point proxy logic[] be invoked” and that “only ‘the CPP is invoked.’”  These statements were an unequivocal and unambiguous surrender of methods invoking the CPP logic in the claims.

Accordingly, if a patent owner has different litigation counsel and IPR counsel it is vital, especially in light of this ruling, that they work together closely to understand how arguments made during the IPR will affect the litigation.  It is imperative that a patent owners’ IPR counsel not make an argument that narrows the scope of the claims so that proving infringement is not viable.

Conversely, a defendant or petitioner challenging a patent’s validity can use the IPR process to require patent owners to take a concrete position on claim construction that could narrow the issues for litigation and provide stronger non-infringement positions.  Because a patent owner’s statements extend to continuation and divisional patents claiming priority to the challenged patent, the ramifications can have a significant impact on the patent owner’s infringement positions.