Addressing for the first time the issue of whether statements made during America Invents Act post-grant proceedings can trigger a prosecution disclaimer, the US Court of Appeals for the Federal Circuit upheld the district court’s ruling that arguments made by a patent owner during an inter partes review (IPR) proceeding can be relied on to support a finding of prosecution disclaimer during claim construction. Aylus Networks, Inc. v. Apple Inc., Case No. 16-1599 (Fed. Cir., May 11, 2017) (Stoll, J).

Aylus Networks filed a patent infringement suit against Apple, alleging that Apple’s AirPlay product/feature infringed its patent. The asserted patent covers systems and methods for streaming and displaying media content using combinations of networked components, including a media server (MS); a media renderer (MR); control point (CP) logic to negotiate media content delivery with the MS and/or MR; and control point proxy (CPP) logic to control presentation of the content and to negotiate with the MS, MR and/or CP logic. In some embodiments, the CP logic and CPP logic cooperatively negotiate media delivery, while in other embodiments only CP or CPP logic is invoked to negotiate media delivery.

Apple filed two separate IPR petitions challenging the asserted patent. Ultimately, the Patent Trial and Appeal Board (PTAB) instituted proceedings on all challenged claims of the patent except claims 2, 4, 21 and 23. In view of the institution, Aylus filed a notice of voluntary dismissal in the district court, dismissing with prejudice its infringement contentions as to all of the asserted claims except claims 2 and 21. Apple subsequently filed a motion for summary judgment of non-infringement as to those claims, relying on Aylus’s statement during the IPR that the claims required invoking only the CPP logic to negotiate media content delivery between the MS and MR. Aylus argued that the proper construction of the claims was not so limited.

When construing the disputed limitation, the district court relied on the statements made by Aylus in its preliminary response to Apple’s IPR petitions, finding the statements “akin to prosecution disclaimer.” Based on these statements, the district court construed the relevant limitation to “require that only the CPP logic is invoked to negotiate media content delivery,” and granted Apple summary judgment of non-infringement. Aylus appealed, arguing that statements made during an IPR cannot be relied on to support a finding of prosecution disclaimer.

The Federal Circuit affirmed the district court’s claim construction and grant of summary judgment. The Court restated the axiom that the prosecution history “includes all express representations made by or on behalf of the applicant to the examiner to induce a patent grant.” It went on to explain that prosecution disclaimer “protects the public’s reliance on definitive statements made during prosecution.” The Court also observed that the doctrine has been applied in the past to statements made during a re-examination proceeding. Based on this historical purpose and usage, the Court concluded that “[e]xtending the prosecution disclaimer doctrine to IPR proceedings will ensure that claims are not argued one way in order to maintain their patentability and in a different way against accused infringers.”

Practice Note: Patent owners should beware that statements made to the PTAB during post-grant proceedings could potentially limit the scope of the challenged claims. A patent owner must ensure that arguments differentiating the challenged claims from the prior art are not at odds with its infringement positions.