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Patent Owner Tip #19 for Surviving an Instituted IPR: Sur-Reply Strategies

In this final patent owner tip for surviving an instituted IPR we discuss sur-reply strategies. At this point, the Patent Owner has filed its Response, developed all the facts and evidence, and taken and defended expert depositions. The Sur-Reply now gives the Patent Owner the last word. The United States Patent and Trademark Office Trial Practice Guide (“PTO TPG”) was revised in 2018, making significant changes to substantive filings, including making filing Sur-Replies a matter of right. The following tips will help you draft an effective Sur-Reply Brief and avoid any pitfalls.

Marshal Your Strongest Rebuttal Arguments and Evidence, but Don’t Restate Positions Already Offered. Patent Owners should marshal their strongest arguments, evidence, and law in response to Petitioners’ most effective arguments, rather than attempt to repeat and reemphasize arguments already included in the Patent Owner Response. The Sur-Reply is a vehicle by which Patent Owners may respond to arguments made in the Petitioner’s Reply, discuss reply declaration testimony, or highlight important cross-examination testimony. Because the Patent Owner has the last evidentiary word, it is also an opportunity to highlight Petitioner’s overall failure of proof, inconsistent testimony from its expert, and any other damaging testimony from cross-examination. It should also be viewed as the final opportunity to educate the Board and correct any potential misinterpretations of evidence prior to the oral hearing.

Do Not Attempt to Offer New Evidence, Arguments, or Theories. Sur-Replies “may not be accompanied by new evidence other than deposition transcripts of the cross-examination of any reply witnesses.” PTO TPG at 14. Although the Patent Owner has the benefit of the final word in the IPR proceeding, it is still bound by the record and cannot offer new evidence, arguments, or theories not already presented either in the Patent Owner’s Response, the Petitioner’s Reply or where the Petitioner addressed aspects of the Institution Decision. This highlights an issue previously discussed in a prior blog post, recognizing the uneven evidentiary playing field in IPRs. For example, Petitioners are entitled to introduce deposition transcripts into the record, but if Petitioner declines to do so, Patent Owner is expressly barred from presenting such evidence in its Sur-Reply. The Patent Trial and Appeal Board (“the Board”) may not consider new or belatedly presented issues in a Sur-Reply, and as the PTO TPG admonishes, “[t]he Board is not required to sort proper from improper portions of the reply or sur-reply.” Id. at 15.

The Sur-Reply is the opportunity for the last evidentiary word. Using the strategies and avoiding the pitfalls noted above will help Patent Owners crystalize issues for decision and highlight failures of proof in the Petitioner’s Reply.


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Brad M. Scheller is an experienced patent litigator and strategic counselor to start-up ventures and established businesses in the mechanical and electrical arts, with a focus in EV and battery technologies and advising clients on patent portfolio growth, management and enforcement. He represents clients before the United States Patent and Trademark Office and as lead counsel in federal district court and appellate litigation across the country.
Courtney Herndon is an Associate in Mintz's Intellectual Property Practice. Before joining Mintz, Courtney clerked for Associate Justice Geraldine Hines of the Massachusetts Supreme Judicial Court and Associate Justice Vickie L. Henry of the Massachusetts Appeals Court.