On March 31, 2016, the United States Patent and Trademark Office (USPTO) issued final rules implementing several changes and clarifications to the rules governing trial proceedings before the Patent Trial and Appeal Board (PTAB), including inter partes, post grant and covered business method review proceedings, as well as derivation proceedings.1 These final rules are adopted from the rules proposed in August 2015 and reflect public comments both before and after those rules were proposed. The rules changes are of interest to stakeholders in the patent system—both patent owners and prospective patent challengers—as they reflect ongoing changes to the PTAB trial proceedings that have become an important part of patent litigation in the United States.

Testimonial Evidence Submitted with a Preliminary Response

In the final rules issued yesterday, the USPTO removed the prohibition on new testimonial evidence submitted with a patent owner’s preliminary response from 37 C.F.R. §§ 42.107 and 42.207. Any evidence may now be used in support of the preliminary response. The amended rules state, however, that “any genuine issue of material fact created by such testimonial evidence [submitted with a preliminary response] will be viewed in the light most favorable to the petitioner solely for purposes of deciding whether to institute an inter partes [or post-grant] review.” Sections 42.108 and 42.208 allow petitioners to request leave to file a reply to a preliminary response, which may be granted on a showing of good cause.

Claim Construction

The USPTO amended sections 42.100 and 42.200 to specify that the broadest reasonable interpretation standard for claim construction, which applies to unexpired claims in inter partes and post-grant review proceedings, does not apply if the claims will expire before the final written decision. To that end, the amended rules permit parties to request that the PTAB apply “a district court-type claim construction approach” for patents that will expire within 18 months of the entry of the notice affording a filing date to a petition. Such requests must be made by motion within 30 days following the petition’s filing.

Duty of Candor Requirements

The new rules further clarify the duty of candor requirements on counsel and parties appearing in PTAB trial proceedings. In particular, 37 C.F.R. § 42.11 now expressly incorporates the requirements of § 11.18(a) and (b)(2) that apply generally to signatures before the USPTO. Thus, the signature of a paper is a certification that “[t]o the best of the party’s knowledge, information and belief, formed after an inquiry reasonable under the circumstances”:

  • the paper is not submitted for an improper purpose;
  • the averments and denials have (or, after further investigation or discovery, are likely to have) evidentiary support; and
  • the legal contentions are warranted by existing law or a nonfrivolous argument to change existing law.

These certification requirements are similar to those imposed in federal district courts by Rule 11 of the Federal Rules Civil Procedure.

The rules also specify that the PTAB may enforce the requirements with sanctions for their violation, either upon a motion by the opposing party or on the PTAB’s own initiative. The procedures associated with motions and sua sponte orders seeking to impose such sanctions are, again, similar to those provided in Rule 11 of the Federal Rules of Civil Procedure.

Other Procedural Changes

The new rules also replace page limits with word count limits for petitions, preliminary responses, patent owner responses and replies to petitions. Previously, petitions, preliminary responses and patent owner responses were limited to 60 pages in inter partes reviews and derivation proceedings and 80 pages in post-grant reviews (including covered business method patent reviews). Under the new rules, these papers will be limited to 14,000 words or 18,700 words in the respective proceedings. Replies to petitions, which were previously limited to 25 pages in any proceeding, will be limited to 5,600 words. This will allow parties to include arguments in claim charts and avoid certain formality requirements under the previously issued rules.

The new rules also amend section 42.23(b) to explicitly preclude raising new arguments in replies to patent owner responses or preliminary responses. The PTAB frequently applied this restriction through its case-by-case jurisprudence, even though the prior rule only referred to motions, but it is now expressly included in the rule.

The new rules also change the required time for serving demonstrative exhibits from 5 business days before oral argument to 7 business days before oral argument.


The changes to the rules governing America Invents Act (AIA) trial proceedings reflect the USPTO’s ongoing effort to improve the adjudication of these still-new proceedings. Other changes that the USPTO considered during the public comment period, such as changes relating to discovery and the procedure for amending claims, were ultimately rejected in favor of allowing the PTAB’s jurisprudence develop on a case-by-case basis. Nonetheless, the changes that were made will likely have a significant impact on practice before the PTAB in at least some cases. And the rules and their application should continue to evolve as a result of future rules changes and appellate decisions from both the US Court of Appeals for the Federal Circuit and the US Supreme Court.

1 The final rules were published in the Federal Register on April 1, 2016. See Amendments to the Rules of Practice for Trials Before the Patent Trial and Appeal Board, 81 FR 18750 (Apr. 1, 2016).