In inter partes review (IPR) proceedings, the petition and patent owner's response generally define the scope of the parties' arguments. This scope generally limits a petitioner or patent owner's ability to raise new arguments in subsequent papers, such as a reply or sur-reply, or at an oral hearing. For petitioners, a reply generally "may only respond to arguments raised in . [a] patent owner preliminary response, patent owner response, or decision on institution," and those reply arguments are often bounded by the positions taken in the initial petition. For patent owners, arguments not raised in its patent owner response may be deemed waived if raised later, and the sur-reply "may only respond to arguments raised in the corresponding [petitioner] reply." If the Patent Trial and Appeal Board (Board) determines that a party is making untimely arguments, it may decline to consider them on the merits.

On appeal, some parties have also challenged the Board's consideration of new arguments under the Administrative Procedure Act (APA). The Federal Circuit will usually review the Board's determination not to consider an argument because it was untimely for abuse of discretion, and consider whether the Patent and Trademark Office (PTO) provided adequate notice to the other party and an opportunity to respond. 

A party also generally cannot raise new arguments on appeal to the Federal Circuit, whose review is constrained to the record before the Board. The Federal Circuit may find an argument raised for the first time on appeal to be waived because it lacks "the benefit of the [Board]'s informed judgement" on the issue.

In each scenario, the key question comes down to what constitutes a "new" or untimely argument. This paper reviews recent decisions addressing whether new arguments were raised during an IPR and on appeal and examines how to identify and respond to potential new arguments.

Read "Identifying Impermissible New Arguments and Their Effect on IPR Proceedings and Appeals" here.

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.