Canada: Microsoft v. Proxyconn: Broadest Reasonable Interpretation Revisited

Last Updated: July 1 2015
Article by Ken Bousfield

Microsoft Corporation v. Proxyconn Inc., Federal Circuit, June 16, 2015.

In an appeal by both sides from a decision of the Patent and Trademark Appeal Board in a post-issue Inter Partes Review proceeding brought by Microsoft against Proxyconn's processing claims, the Federal Circuit both gives and takes away.

Federal Circuit reasonably interprets Broadest Reasonable Interpretation

During prosecution before the Patent and Trademark Office, Examiners are to apply the rule of "Broadest Reasonable Interpretation" to the claim terminology being examined, as it would be understood by a person of ordinary skill in the art field of the invention. The standard applies both to the claim language and to interpretation of the prior art. In general, the customary and ordinary meaning of the claim term in the art is to apply unless the inventor indicates otherwise. As affirmed in Proxyconn, Broadest Reasonable Interpretation also applies to IPR proceedings.

Examiners may tend to be persons skilled in the art of examining patent application, as opposed to being persons skilled in the arts being examined. Since reasonableness often lies in the eye of the beholder, this can be an important distinction.

Although interpretation under the rule of Broadest Reasonable Interpretation is supposed to be as made through the eyes of a person skilled in the art, PTO interpretation has sometimes tended toward any meaning that a clever Examiner can imagine. Every practitioner is familiar with rejections under 35 USC 102 and 35 USC 103 that rely on remarkably creative interpretations of claims and of the prior art. On occasion, interpretations may be sufficiently imaginative to contradict the cited reference. The interpretations may be extraordinarily clever, if not ingenious. However, "ingenious" is not the standard under the law. Nor is the standard based on seeing the invention through the eyes of a highly skilled Examiner.

In that context, Proxyconn will come as a welcome balm to practitioners everywhere.

Proxyconn objected to use of "Broadest Reasonable Interpretation" as the standard for claim interpretation. Given the right to amend claims in an IPR, the Federal Circuit affirmed that "Broadest Reasonable Interpretation" is the correct standard in IPR proceedings.i In affirming its earlier decision, the Court emphasized that "reasonable" is not a mere suggestion:

"This is not to say, however, that the Board may construe claims during IPR so broadly that its constructions are unreasonable ..."

"The protocol of giving claims their broadest reasonable interpretation ... does not include giving claims a legally incorrect interpretation".

"The broadest-construction rubric coupled with the term 'comprising' does not give the PTO an unfettered license to interpret claims to embrace anything remotely related to the invention".ii

"A construction that is "unreasonably broad" and which does not "reasonably reflect the plain language and disclosure" will not pass muster."iii

"Even under the broadest reasonable interpretation, the Board's construction "cannot be divorced from the specification and the record evidence."iv

[The broadest reasonable interpretation] "must be consistent with the one that those skilled in the art would reach"v

By emphasizing that reasonableness is not limitless and that claim language must be viewed through the eyes of a person of skill, the Court is attempting to rein-in the very great elasticity of Broadest Reasonable Interpretation as applied in the PTO.

Heartwarming as the Proxyconn decision may be, the connection between Federal Circuit precedent and actual day-to-day practice in the PTO can sometimes be largely theoretical.  Nonetheless, the essence of the human condition is to live in hope.

Amended Claims Must Clear All References of Record, Cited or Not

In another issue of practical importance, Proxyconn had introduced two new claims, based on two existing claims. In rejecting the new claims, the Board applied a prior art reference of record in the case that had not been relied upon in challenging the two original claims. Proxyconn argued that its new claims were allowable over the references advanced against the existing claims, and that it was not obliged to overcome objections that had not been made.

The Board disagreed. The Federal Circuit affirmed.

The point highlights a trap for the unwary.

Non-broadening amendments may be presented in an IPR. However, the opportunity is limited, and does not include an ability to amend after new objections by the Board.

The Court noted that the art was of record, was well known, and had been a source of contention in respect of other claims in the IPR, implicitly suggesting that the patent owner had received a full and fair chance to present its position, including at the hearing.

While it may not sound unreasonable that newly presented claims should distinguish all the art of record, the very uncertainty of claim and prior art interpretation may make that exercise a challenge of rather fine skill and judgment. Given the lack of further opportunity to amend or reply, there is a strong incentive to err on the side of caution.  Yet excessive caution may cede important claim scope to the public (i.e., to competitors) unnecessarily. The resultant claims may then be worthless.

In light of Proxyconn, in an IPR a patent owner must be careful to explain not only why the new or amended claim is patentable over art cited in known objections that were actually made, but also to foresee and to overcome, any unknown rejections that might have been made on the basis of other art of record. In Proxyconn, The Federal Circuit has placed the burden of risk in this highly skilled alchemy, or crystal ball analysis, squarely on the patent owner.


i The Court relied cited its own decision In re Cuozzo Speed Techs., LLC, 778 F3d 1271 (Fed. Cir. 2015)

ii In re Suitco Surface, Inc., 603 F.3d 1255, 1260 (Fed. Cir. 2010).

iii Suitco, supra, at 1260.

iv In re NTP, Inc., 654 F.3d 1279, 1288 (Fed. Cir. 2011).

v In re Cortright, 165 F.3d 1353, 1358 (Fed. Cir. 1999)

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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Ken Bousfield
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