Post-Grant Review Lawyers

Post-grant reviews offer a critical opportunity to challenge the validity of a patent shortly after its issuance and on a broad array of bases. This provides a strategic tool for business to protect their technological assets. Based out of Washington, D.C., our team of attorneys brings a sophisticated blend of technical and legal acumen to the table. With degrees in engineering, computer science, biochemistry and molecular biology, coupled with deep legal experience, we are uniquely positioned to navigate the complexities of post-grant reviews and other PTO post-issuance proceedings.

Our attorneys at PV Law LLP have over 100 years of collective experience in patent enforcement and U.S. trade law to deliver Big Law patent experience with cost-effective solutions. Whether you are facing challenges to your patents or need to contest the validity of others, our multilingual team, fluent in English, Korean and Chinese, is ready to support clients across the globe with sophisticated, knowledgeable legal advocacy.

Understanding The Post-Grant Review Process

The post-grant review process is similar to inter partes review and allows third parties to challenge the patentability of claims recently granted by the USPTO. A request for post-grant review must be filed within nine months of the initial granting of the patent or a reissue of the patent. The petition can raise grounds that are not available in, for example, inter partes review and ex parte reexamination, for example, grounds alleging unpatentable subject matter under § 101, lack of novelty and obviousness under §§ 102 and 103 (including based on product prior art), and lack of enablement or written description support and indefiniteness under § 112.

For a post-grant review proceeding to be initiated, the challenging party must show that the challenged patent claims are more likely than not to be unpatentable. The owner of the patent at issue has three months after the PTAB issues a notice that a filing date for the petition has been granted to file a preliminary response to the petition. Similar to inter partes reviews, the parties may separately brief whether the PTAB should deny the petition on discretionary grounds. The PTAB has three months from the patent owner’s preliminary response to decide whether to institute review. If a proceeding is instituted, the PTAB will make a final decision within one year of institution, with a possible extension for good cause no longer than six months.

How Do The Grounds For Post-Grant Review Differ From Inter Partes Review?

Post-grant review allows a wider range of validity challenges than inter partes review, making it the most comprehensive administrative option immediately after a patent is issued. A petitioner may raise any ground of invalidity based on 35 U.S.C. § 101 (subject matter eligibility), 35 U.S.C. § 112 (written description, enablement and definiteness), along with prior art arguments, including based on product prior art.

By contrast, inter partes review is limited to prior art challenges under §§ 102 and 103, based only on patents and printed publications. It does not permit arguments under § 101 or § 112.

This broader scope gives post-grant review a distinct strategic advantage. A patent may withstand prior art scrutiny yet still fail due to insufficient disclosure or ineligible subject matter. Post-grant review allows those foundational issues to be addressed directly.

While the scope of available challenges under post-grant review is wider, the time to bring such challenges is narrower. Specifically, a petition must be filed within nine months of issuanceAfter that period, parties generally must rely on narrower proceedings such as inter partes review.

For both challengers and patent owners, the distinctions between post-grant review and inter partes review affect how disputes are framed, what arguments are preserved and how early decisions shape long-term enforcement or defense strategy.

Who Can File For A Post-Grant Review?

A post-grant review can be filed by any person who is not the patent owner and has not previously filed a civil action challenging the validity of a claim of the patent. This review process must be initiated within nine months of the patent’s grant date or reissuance. It is a powerful tool for companies and individuals who believe that a patent granted by the United States Patent and Trademark Office (USPTO) should not have been issued due to issues like prior art or other patentability criteria.

What Is The “More Likely Than Not” Standard For Institution Of A Post-Grant Review?

The “more likely than not” standard is the threshold requirement that a petitioner must satisfy to have a post-grant review instituted by the Patent Trial and Appeal Board.

This standard serves as a critical gatekeeping function. It requires more than a speculative or conclusory argument but does not demand proof sufficient to prevail on the merits. Instead, the petitioner must present a well-developed case supported by legal reasoning, factual evidence and, in most cases, expert testimony. The petition must clearly articulate why the claims fail under the asserted statutory grounds, whether under §§ 101, 102, 103 or 112.

In practice, meeting this standard requires careful preparation at the outset. Petitioners typically rely on detailed claim analysis, prior art references where applicable, technical declarations and structured legal arguments that align with the statutory framework. The Board evaluates whether these materials collectively establish a likelihood of unpatentability before deciding whether to proceed.

If the standard is met, the PTAB institutes the review and the proceeding moves into a trial phase. This phase includes briefing, limited discovery and oral argument, culminating in a final written decision.

The importance of this threshold cannot be overstated. The petition must stand on its own at the institution stage, and there is limited opportunity to supplement arguments later. A failure to meet the “more likely than not” standard results in denial of the petition, effectively ending the challenge before it begins. For this reason, the initial filing is often the most consequential step in the entire post-grant review process.

Can You Appeal A Final Decision In A Post-Grant Review?

A final decision made in a post-grant review usually can be appealed. If parties involved are dissatisfied with the decision of the Patent Trial and Appeal Board (PTAB), they have the option to appeal to the United States Court of Appeals for the Federal Circuit. This appeal must be filed within a specified period after the decision is rendered. The appeal process allows the Federal Circuit to review the PTAB’s findings and conclusions on both factual and legal grounds. At PV Law, our attorneys are well-versed in navigating these complex appellate procedures.

What Type Of Discovery Is Allowed During A Post-Grant Review?

During the discovery process, if declaration testimony has been submitted, then the declarant could be subject to cross-examination.

In some cases, parties may want to go through additional discovery. They can do this together, by mutual agreement, or one party can use an authorized motion. Once this motion has been filed, it can make the request for additional discovery, even without the mutual cooperation of the other party. This does not mean it will be granted, but it is important for involved parties to know that they can take this step on their own if they believe it is necessary to gather the proper information relating to the case. That being said, discovery is usually much more limited than it would be in a district court proceeding.

What Are The Unique Risks Of Post-Grant Review Estoppel?

Post-grant review provides a broad opportunity to challenge patent validity, but it also creates significant estoppel risks that can affect future proceedings. Under 35 U.S.C. § 325(e), once a final written decision is issued, the petitioner may be barred from raising certain arguments again in later litigation or administrative actions.

Key estoppel risks include:

• Broad preclusion of arguments: Estoppel applies to issues that were raised or reasonably could have been raised during the review. This requires petitioners to present all viable grounds at the outset, as omitted arguments may be permanently lost.
• Effect on court litigation: In cases in federal court or at the International Trade Commission, estoppel can limit defenses available later. Arguments addressed or available in the post-grant review may not be revisited, narrowing litigation strategy.
• Risk of reinforcing patent validity: If the PTAB upholds the patent claims, the final decision can strengthen the patent. This may affect negotiations, enforcement efforts and the likelihood of success in future challenges.

Understanding these risks is essential before initiating a post-grant review.  Petitioners must take a comprehensive approach to filing. This often involves detailed technical and legal analysis early in the process to avoid gaps that could later restrict options. While the process offers a powerful way to challenge patents early, it also requires careful planning to avoid limiting future legal options.

Sophisticated And Effective Post-Grant Review Representation

At PV Law, our post-grant review lawyers will provide the legal guidance you need throughout the process to protect your intellectual property or your products. You can trust us to use our technical knowledge and legal experience to your advantage.