Getting the Last Word in PTAB Trials

Every brief in a PTAB trial has a defined job. The petitioner bears the burden of proving unpatentability, but the patent owner usually files the last merits paper. That sequence, and the limits on what each paper may contain, shape strategy on both sides.

This article maps the briefing sequence in inter partes review (IPR) and post-grant review (PGR) and explains the rules that keep later papers from becoming a second petition.

The briefing sequence

A typical trial proceeds in this order:

1. Petition. The petitioner sets out each ground, the claim construction it relies on, and its supporting evidence, including expert declarations.
2. Preliminary response (optional). The patent owner may argue that trial should not be instituted.
3. Reply and sur-reply on institution issues (only if authorized). The Board sometimes authorizes a short petitioner reply and patent owner sur-reply before institution, for example on a discretionary-denial or time-bar question.
4. Institution decision. If trial is instituted, the scheduling order sets the remaining dates.
5. Patent owner response. The patent owner’s full merits response, with any declarations, and any motion to amend.
6. Petitioner reply. A response to the patent owner response, often with a reply declaration.
7. Patent owner sur-reply. The last merits brief.
8. Motions to exclude evidence, with oppositions and replies.
9. Oral hearing, followed by the final written decision.

Motion-to-amend briefing runs on a parallel track with its own sequence. Procedures for amendments have changed several times, so check current USPTO guidance.

Sur-replies replaced observations

Before the sur-reply existed, a patent owner had no general right to respond in writing to the petitioner’s reply. Instead, parties used “motions for observation” to point the Board to cross-examination testimony of the other side’s reply witness. The Trial Practice Guide updates of 2018 and 2019 introduced the sur-reply and replaced motions for observation on cross-examination with it. The sur-reply now serves both functions: it responds to the reply and can point to cross-examination testimony.

What a reply may contain

Under 37 C.F.R. § 42.23(b), a reply may only respond to arguments raised in the corresponding opposition or patent owner response (and, in appropriate contexts, the preliminary response or institution decision). The reply is not an opportunity to present the case the petitioner should have made in the petition.

The Board and the Federal Circuit have drawn a line between:

• Legitimate responsive argument and evidence, such as rebutting the patent owner’s claim construction, answering criticism of an expert, or explaining how the cited art meets a limitation in light of the patent owner’s arguments; and
• New theories, such as a new combination of references, a new ground, or reliance on a different portion of the art to fill a gap the petition never addressed.

New arguments or evidence in a reply can be disregarded. The petitioner’s best evidence therefore usually needs to be in the petition.

What a sur-reply may contain

Under current guidance, a sur-reply may respond only to arguments made in the reply, comment on reply declaration testimony, and point to cross-examination testimony. A sur-reply may not be accompanied by new evidence other than deposition transcripts of the cross-examination of a reply witness. A patent owner that wants to rely on new expert testimony generally needs to have filed it with the patent owner response.

Demonstratives at the oral hearing

Parties exchange demonstrative exhibits before the oral hearing and may object to each other’s slides. Demonstratives are aids to argument, not evidence. They cannot introduce new evidence or new argument, and the Board may decline to consider slides that go beyond the record. Objections to demonstratives are often resolved at or before the hearing.

The hearing itself is also limited to arguments already in the papers. A point made for the first time at oral argument is unlikely to be considered.

Strategy considerations

Some considerations parties commonly weigh:

• Front-loading the petition. Because the reply is limited, petitioners often anticipate likely patent owner arguments, such as claim construction disputes, in the petition itself.
• Building the response record. Because the sur-reply generally cannot carry new evidence, patent owners often put their full expert testimony into the patent owner response.
• Cross-examination timing. Testimony obtained in the deposition of a reply witness can be cited in the sur-reply, which makes that deposition significant. See evidentiary considerations in PTAB trials.
• Policing scope. A party that believes the other side’s paper exceeds its permitted scope may raise the issue in its own brief or ask the Board for guidance, rather than in a motion to exclude, which addresses admissibility.
• Supplemental information. New information that becomes available after institution may come in through a separate motion. See supplementing the record.

Key takeaways

• The patent owner’s sur-reply is usually the last merits brief, followed by evidentiary motions and the oral hearing.
• Under § 42.23(b), a reply may only respond to arguments raised in the corresponding opposition or response; new material can be disregarded.
• Sur-replies, introduced in the 2018–2019 Trial Practice Guide updates in place of motions for observation, may not add new evidence beyond reply-witness deposition transcripts.
• Demonstratives at the hearing cannot introduce new evidence or argument.