An inter partes review, or IPR, is a legal procedure conducted by the Patent Trial and Appeal Board (PTAB) of the United States Patent and Trademark Offices (USPTO). They use it to assess the patentability of specific claims within a patent. This review is limited to challenges based on the criteria defined under sections 102 or 103, specifically focusing on prior art comprised of patents or printed publications.

The IPR process commences when a third party, typically represented by an inter partes review lawyer, files a formal petition. This third party must not be the patent owner and must submit their petition either nine months after the patent’s issuance or after the conclusion of a post-grant review if initiated.

Subsequently, the patent owner may choose to respond with a preliminary statement. The PTAB then evaluates whether there’s a reasonable likelihood that the petitioner will succeed in challenging at least one claim. If the review is not dismissed and does proceed, the PTAB issues a final determination within one year, with the possibility of a six-month extension for valid reasons. This process was implemented on September 16, 2012, and applies to patents issued before, on, or after that date.

What Is an Inter Partes Review?

It’s natural to wonder what an inter partes review entails. It’s essentially a mechanism through which an interested party can dispute the validity of a patent’s claim. Read on for a breakdown of the key aspects of an inter partes review – what can be challenged, who can file, the timing involved, the associated costs, and more.

When Can You File an Inter Partes Review?

To initiate an IPR, one must allege the invalidity of at least one patented claim, citing grounds such as anticipation or obviousness (sections 102 or 103). The evidence is limited to patents and printed publications. The key requirement is demonstrating a reasonable likelihood of success in challenging at least one claim. A comprehensive petition, within a 14,000-word limit, can also incorporate supporting declarations or affidavits.

Filing the Inter Partes Review

An IPR can be filed by anyone who isn’t the patent owner and hasn’t already initiated a civil action challenging the patent’s claim. Furthermore, counterclaiming for invalidity in an infringement lawsuit doesn’t preclude one from filing an IPR.

Timeline for an IPR Petition

Filing an IPR petition is possible nine months after a patent’s grant. However, if a post-grant review (PGR) is in progress, the IPR petition has to wait until the PGR concludes. There are exceptions for patents issued under the First-to-Invent system.

When concurrent civil proceedings are in motion concerning the patent, a defendant in a patent infringement suit must file an IPR petition within one year of being served with a summons. This is important to avoid being barred from the IPR process. 

Additionally, the USPTO may impose annual limits on the number of IPR petitions in the first four years, making early filing essential.

Costs Associated with Filing an Inter Partes Review

The cost of filing an IPR petition is $9,000 for challenging up to 20 claims, with an additional $200 for each extra claim. In case the petition is granted, a post-institution fee of $14,000 must be paid for up to 15 claims. There is an additional charge of $400 for each claim thereafter.

Patent Owner’s Preliminary Response

Upon receiving notice that an IPR petition has been granted a filing date, the patent owner has the option to file a Preliminary Response. This response focuses on reasons why the IPR should be denied institutions. It’s important to note that the preliminary response is not mandatory. The deadline for filing the preliminary response is three months from the notice date.

Institution of the Inter Partes Review

A pivotal moment in an IPR is the institution phase. The PTAB evaluates the petition and determines whether there is a reasonable likelihood that at least one challenged claim is unpatentable. If so, the PTAB may institute the IPR. They have the discretion to institute or deny specific claims. The PTAB’s final determination is expected within one year of the institution.

Patent Owner’s Response After Institution

After the IPR is instituted, the patent owner can file a response addressing the grounds covered by the institution. This response must be filed within three months from the date of institution. Additionally, the patent owner has the option to file claim amendments, which should be submitted with the response.

If you require further legal guidance related to your specific inter partes review, it’s advisable to consult an experienced inter partes review lawyer.

Reach Out to a Seasoned Inter Partes Review Lawyer for Legal Guidance

An inter partes review is a vital mechanism for ensuring the integrity of patents, allowing interested parties to question their validity through established legal channels.

Engaging an attorney can be instrumental in navigating these complex proceedings and ensuring that the patent owner’s rights and interests are well-protected throughout the IPR process.If you need reliable legal intervention in your matter, consult the proven inter partes review lawyer at Emerson Thomson Bennett, LLC. Call 330-434-9999 or fill out our online form today to schedule a free consultation.



We provide complete intellectual property representation to business owners, inventors and artists in all matters related to the establishment and protection of domestic and international patents, trademarks and copyrights. Attorneys at our firm also serve as in-house IP counsel for companies whose needs do not call for a full-time internal position.

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