Crossing the Chasm: Avoiding and Surviving the PTAB

In 2012, the American Invents Act established three new administrative procedures: post grant review (PGR), inter-partes review (IPR), and covered business method patent (CBM) review. In each of these proceedings, anyone may file a petition challenging the validity of an issued patent. Patent practitioners have long been trained to draft patents that survive litigation. It is no secret that most asserted patents now end up before the PTAB, and the PTAB tends to use different rules that favor the challenger. What have the last five years taught us to survive this new reality?

Knock Out the Challenger

Only about 30% of IPR petitions are dismissed without trial. Petitions are most often dismissed because the challenger’s invalidity arguments are incomplete or unsupported, or that the challenger has failed to construe the claims properly. Patentees can use several strategies to win at this earliest stage.

Avoid Broadest “Un-Reasonable” Interpretation

In Cuozzo Speed Technoloogies v. Lee, 579 U.S._, 136 S. Ct. 2131 (2016), the Supreme Court unanimously held the PTAB was within its discretion to apply a “broadest reasonable interpretation” (BRI) standard when interpreting claims – counter to the “ordinary and customary meaning” standard applied by the courts. Patentees should now expect their claims will be subject to BRI. Under BRI, claim terms are given the broadest reasonable interpretation in light of the specification.

The best way for a patent owner to avoid an unfavorable BRI is to have a thorough and well-described specification. This runs counter to strategies of old, when some practitioners believed that obscuring the explanation of the invention or using nonsensical words in the claims might form a basis for catching more infringers.

Patent prosecutors often focus on one or two aspects of an Examiner’s rejection, the rationale being “the less said, the better” to avoid file wrapper estoppel. However, with claims always subject to BRI, it may not be wise to let an Examiner’s erroneous interpretation stand. Even if the argument is not dispositive of the issue at hand, better to have any “unreasonable” interpretation clarified on the record before the patent issues.

Anticipate the Obvious

Issued patents enjoy a presumption of validity when they are tested before a Federal judge or jury. Now with the PTAB as the first stop, challengers need only show unpatentability by a “preponderance of the evidence.” The patent owner must assume that an opponent will establish that prima facie case by showing all claim elements are present in two or more prior art references.

KSR international v. Teleflex, 550 U.S. 398 (2007) severely reduced the ability of patentees to argue there is no “teaching, suggestion or motivation” to combine references. However, even in the context of a PTAB proceeding, the bedrock principle of avoiding improper hindsight still applies. Even if the petitioner can establish a prima facie case, they must still demonstrate the problem was known in the prior art, not gleaned from the specification, and without using hindsight.  See, e.g., Purdue Pharma LP v. Depo-Med (Fed. Cir., 2015-2029, March 26, 2016).

Therefore, one way to rebut a post-grant petition is to explain in the specification the problem solved, and how the prior art falls short. Even if a challenger can establish a prima facie case, your chances of dismissal are greatly improved by showing the problem solved was gleaned from the prior art rather than from the specification itself.

Rejections? –  Don’t Worry, Be Happy

A robust prosecution may also help avoid a post-grant proceeding entirely. For example, a restriction requirement establishes that different sets of claims are patentably distinct and can be used to “protect” one set of claims from another set that is invalidated in a post-grant proceeding.

Vetting subject matter eligibility and written description/enablement issues during prosecution may also help avoid a post-grant proceeding. For example, addressing a Section 101 eligibility  or Section 112 written description issue when there is ample opportunity to present legal arguments and amend claims can eliminate one or more bases for the challenger.

Surviving the Battle

Adding Evidence – More Is More

Before the PTAB, patent owners avoided the use of declarations unless absolutely necessary. That “less is more” strategy should now be reconsidered. The PTAB expects petitions and motions to be accompanied by expert declarations supported by underlying facts or data.  Fed. Reg. Vol. 77, No. 157, 48763 (August 14, 2012); See, e.g., Ariosa, IPR2013-00276 (P.T.A.B. Jan. 13, 2016).  Placing such evidence on the record during prosecution provides the patent owner with a tool to rely upon later. This is especially important given the tight deadlines, limited opportunities to add expert evidence to the record, and limited ability to amend claims during a post-grant proceeding.

Similarly, the patent owner should retain documents and other evidence that may be useful in overcoming PTAB challenges down the road. For example, evidence of commercial success may be quite useful in overcoming an obviousness challenge.  It is also imperative to maintain good records of inventive activity, including the scope of any public disclosures, to retain the ability to invoke grace periods that can remove a reference as prior art.

Be Precise – or Be Prepared to Lose

Vague language is a target for both prior art and written description/enablement challenges.  Defining terms in the specification is one approach. But consider supporting your preferred claim interpretations and definitions by submitting references, data and declarations testimony into the record during prosecution. As discussed above, clarifying these issues before the examiner may not only avoid a post-grant challenge, but can also help a patent survive after a challenge is instituted.

Rethink Old Enforcement Strategies

PTAB proceedings now almost always accompany district court litigation, and are often filed by defendants in response to a patent infringement complaint. Despite whatever the original intent of Congress was, PTAB proceedings inevitably increase the cost, uncertainty, and complexity of resolving a dispute. Worse, they can derail an enforcement strategy entirely.

One tactic for patent owners is to consider delaying district court litigation until after certain time limits. For example, a PGR can be filed on any grounds other than best mode. By delaying the filing of a complaint until after the 9 month deadline for filing a PGR, the patent owner limits their exposure to an IPR challenge based on prior art only. Another tactic for the patent owner is to thoroughly vet any claims against a post-issuance prior art search before filing a complaint. It may be prudent to assume the best prior art was not of record before the patent examiner, and use as much time as possible to plan your response to the inevitable obviousness challenge.


As we approach the five year anniversary of the PTAB, patent practitioners should reconsider long-held strategies. BRI and evidence standards adopted by the PTAB make surviving post-grant proceedings especially challenging. Pursue a narrowly-focused patent with clear and unambiguous terms, to avoid post-grant proceedings or survive them when instituted. A robust prosecution that addresses a range of issues, corrects Examiner’s errors, and places evidence on the record helps achieve the same goals.


Warning & Disclaimer: The pages, articles and comments on do not constitute legal advice, nor do they create any attorney-client relationship. The articles published express the personal opinion and views of the author as of the time of publication and should not be attributed to the author’s employer, clients or the sponsors of Read more.

Join the Discussion

3 comments so far.

  • [Avatar for Edward Heller]
    Edward Heller
    September 15, 2017 05:18 pm

    Another point, challenge the constitutionality of the proceeding or risk waiver.

    The case law grows that TC Heartland was not a “change” in the law providing an exception to waiver, and that failure to object to venue or to continue to object to venue constitutes a waiver. KONINKLIJKE PHILIPS NV v. Asustek Computer, Inc., CA No. 15-1125-GMS (D. Del. July 19, 2017).

  • [Avatar for Pro Se]
    Pro Se
    September 15, 2017 03:17 am

    “challengers need only show unpatentability by a “preponderance of the evidence.”

    And they will accept 10 references to comprise the parts of a full claim to do it.. the equivalent of using a dictionary to invalidate the copyright of a novel…

    IPRs is nothing more than a game of ratio.. every patent will get nabbed by the 3rd to 4th sequential challenge on the same patent:

    The same administrative judges will get those 3-4 challenges on the same patent and eventually feel it’s their duty to show impartiality and will institute you.. no matter how strong your patent claims are..

    And this is the silent gimmick of the IPR that big buck infringers know. They give their lit managers $300,000 to pop off $20,000 IPR challenges authored by Indian outsourcing and that budget is going to eventually kill your patent.

    I’ve yet to see a patent survive non-Institution past 4 petitions.

    Just remember folks: the PTAB accepted 10 references to force me into institution, on the 4th challenge to my portfolio..

    No one with a valuable patent gets through without damage.

    The Bunch Of Balloons guy’s tragedy, it just really gets no more writing on the wall than that.

  • [Avatar for Dan Hanson]
    Dan Hanson
    September 14, 2017 12:26 pm

    A word about the “broadest reasonable interpretation” (BRI) standard: as this column correctly notes, the interpretation must be reasonable in light of the specification. Resorting to the broadest possible interpretation, without regard to reasonableness or the specification, is not the correct way to proceed. Also, the Straight Path opinion (806 F.3d 1356 (Fed. Cir. 2015)) indicates that in some cases, the BRI standard is so close to the Phillips standard that it doesn’t make a difference which standard is used.