United States: Statements Made in IPR Preliminary Responses May Trigger Later Prosecution Disclaimer

Aylus Networks, Inc. v. Apple Inc., No. 2016-1599 (Fed. Cir. May 11, 2017)

In a case of first impression, the U.S. Court of Appeals for the Federal Circuit has held that a patent owner's statements made in a preliminary statement during an AIA inter partes review (IPR) proceeding may create prosecution disclaimer during subsequent federal court litigation. The court ruled that IPR proceedings are administrative in nature, and the same policies that support disclaimer based on statements made during examination or reexamination proceedings equally apply to statements made during IPR proceedings.


Aylus Networks, Inc. owns U.S. Patent No. RE 44,412, which covers systems and methods for implementing digital home networks having a control point located on a wide area network. Aylus filed an action against Apple Inc. in the U.S. District Court for the Northern District of California, alleging that Apple's AirPlay feature infringed the '412 patent. Apple responded to the lawsuit by filing two petitions with the U.S. Patent and Trademark Office seeking inter partes review of claims in the '412 patent.

During the IPR, Aylus filed a preliminary response arguing why Apple's petitions should not be instituted. The preliminary responses included statements concerning one limitation in the '412 patent claims, "wherein the CPP logic is invoked to negotiate media content delivery between the MS and the MR[.]" The Patent Trial and Appeal Board (PTAB) instituted review on some challenged claims, but denied review on other claims. After institution, Aylus voluntarily dismissed the district court infringement action as to the claims on which the PTAB instituted review, but continued to litigate two claims as to which the PTAB did not institute review.

Apple then filed a motion for summary judgment of noninfringement of the non-instituted claims. Apple argued that the claims should be construed in light of statements Aylus made in its preliminary response to the Patent Office, and under Apple's proposed construction the accused AirPlay device did not infringe. The district court granted summary judgment, adopting Apple's proposed construction of the disputed term and ruling that Aylus' statements in the IPR response were "akin to prosecution disclaimer." Aylus appealed the summary judgment ruling to the Federal Circuit.

Federal Circuit Rules that Even IPR Statements May Constitute Disclaimer

On appeal, the Federal Circuit affirmed the district court. In a panel decision written by Circuit Judge Stoll, the court held that statements made during IPR proceedings, including in the patent owner's preliminary response, can be used to construe a patent's claims, and may result in a disclaimer of claim scope if the statements are a clear and unmistakable surrender of claim scope.

Prosecution disclaimer occurs when a patent owner, through amendment or argument, "unequivocally and unambiguously disavows a certain meaning to obtain a patent[.]" Slip op. at 8, quoting Biogen Idec, Inc. v. GlaxoSmithKline LLC, 713 F.3d 1090, 1095 (Fed. Cir. 2013). In that event, "the doctrine of prosecution history disclaimer narrows the meaning of the claim consistent with the scope of the claim surrendered." Id.

The Federal Circuit noted that although prosecution disclaimer first was recognized for statements made during examination, it has been applied in other PTO proceedings, including reissue and reexaminations. The court noted that, "[o]ver time, prosecution disclaimer has become a fundamental precept in our claim construction jurisprudence, which promotes the public notice function of the intrinsic evidence and protects the public's reliance on definitive statements made during prosecution." Slip op. at 9 (quotation omitted).

The court ruled that, for the same reasons, statements made during IPR proceedings may result in prosecution disclaimer:

It follows that we should apply the doctrine in IPR proceedings before the PTO. Extending 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. In keeping with the underlying purposes of the doctrine, this extension will "promote[] the public notice function of the intrinsic evidence and protect[] the public's reliance on definitive statements made during" IPR proceedings. [Omega Eng'g, Inc. v. Raytek Corp., 334 F.3d 1314, 1324 (Fed. Cir. 2003)].

Slip op. at 10-11 (citation omitted). The court rejected Aylus' arguments to the contrary. First, the court noted that an IPR proceeding is essentially an administrative, not an adjudicative, proceeding, and thus is similar to examination or reexamination. The court observed that in Cuozzo Speed Technologies, LLC v. Lee, 136 S. Ct. 2131 (2016), the Supreme Court characterized IPR proceedings as a "reexamination" or "second look" at an earlier examination. This, the Federal Circuit concluded,

Because an IPR proceeding involves reexamination of an earlier administrative grant of a patent, it follows that statements made by a patent owner during an IPR proceeding can be considered during claim construction and relied upon to support a finding of prosecution disclaimer.

Slip op. at 12. The appeal court also rejected Aylus' argument that the preliminary statement could not create a disclaimer because it preceded the actual IPR institution decision. For purposes of disclaimer, however, the court found that distinction irrelevant:

An IPR proceeding is a two-step process: the Director's decision whether to institute a proceeding, followed (if the proceeding is instituted) by the Board's conduct of the proceeding and decision with respect to patentability. We have said that an "IPR does not begin until it is instituted," Shaw Indus. Grp., Inc. v. Automated Creel Sys., Inc., 817 F.3d 1293, 1300 (Fed. Cir. 2016), but for the purposes of prosecution disclaimer, we find the differences between the two phases of an IPR to be a distinction without a difference. A patent owner's preliminary response filed prior to an institution decision and a patent owner's response filed after institution are both official papers filed with the PTO and made available to the public. In both official papers, the patent owner can define claim terms and otherwise make representations about claim scope to avoid prior art for the purposes of either demonstrating that there is not a reasonable likelihood that the claims are unpatentable on the asserted grounds or demonstrating that the challenger has not shown by a preponderance of the evidence that the claims are unpatentable on the asserted grounds. Regardless of when the statements are made during the proceeding, the public is "entitled to rely on those representations when determining a course of lawful conduct, such as launching a new product or designing-around a patented invention." Biogen, 713 F.3d at 1095.

Slip op. at 13-14 (quotation omitted).

Finally, the court held that Aylus' statements in the preliminary statements were a clear and unmistakable surrender of claim scope, and thus established a disclaimer for purposes of construing the '412 patent claims. Therefore, the court affirmed the district court's grant of summary judgment.

Practical Significance

A patent owner faces several strategic decisions during AIA trial proceedings. In many instances, the patent owner's best chance to avoid cancellation of challenged claims is to avoid the institution of review. Thus, many patent owners opt to file preliminary statements arguing that no basis for review exists by distinguishing the claims over the prior art. The Aylus decision points out that this strategy is not without risk because any statement made in a preliminary response, including claim construction arguments, may be used later to construe claim language. The Aylus court's analysis likely applies to all statements made during IPR proceedings, as well as statements made in post grant review and covered business method reviews.

In addition, although the Federal Circuit has not addressed the broader issue, patent owners should expect that short of actual disclaimer, all statements made during AIA post grant proceedings, including statements in expert reports, will be considered "intrinsic" evidence that a district court may consider, along with the patent specification and prosecution history, in conducting claim construction.

Originally published May 16, 2017

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