Inter Partes Review (IPR)

April 21, 2021

An IPR is a trial proceeding before the Patent Trial and Appeal Board (PTAB) of the US Patent and Trademark Office (USPTO) for raising patentability challenges against any claims in an issued US patent (including utility, design, and plant patents). Any party (that is not estopped, e.g., due to service of a complaint alleging patent infringement more than a year earlier) other than the patent owner can file an IPR petition, which then begins the general process diagrammed below.

Infographic - Datasource Item: 2020 PTAB Proceeding Timeline

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The USPTO has also recently added patent owner sur-replies as a matter of course, which follow the petitioner reply to patent owner’s response. Motion to amend practice has also evolved recently to include the option of filing an initial motion to amend, receiving preliminary guidance from the Board, and then exercising the option to file a revised motion to amend that addresses the Board’s preliminary guidance. Example timelines showing the patent owner sur-replies and the new motion to amend practice are provided below:

Infographic - Datasource Item: 2020 Revised Timeline

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The only permissible grounds for challenging a patent in an IPR petition are anticipation and obviousness based on prior art patents or printed publications. Additionally, an IPR is only available nine months after a patent has issued (in the nine months directly after patent issuance, a different procedure, post-grant review, discussed below, is available instead).

Within three months of the filing of the challenger’s IPR petition, the patent owner has the option to submit a preliminary response that may include a declaration from an expert. Within three months after the patent owner’s preliminary response (or the date on which such a response was due), the PTAB issues an institution decision in which it evaluates the IPR petition and any preliminary response from the patent owner to determine whether the challenger has established a reasonable likelihood that at least one challenged claim is unpatentable. If the PTAB finds a reasonable likelihood that the petitioner would prevail as to at least one challenged claim, then the PTAB’s institution decision will indicate that an IPR trial has been instituted as to all grounds in the IPR petition. Notably, even if the PTAB finds some deficiencies with certain grounds, as long as the petitioner meets the reasonable-likelihood-of-success standard as to at least one challenged claim, then the trial will proceed as to all grounds raised in the IPR petition.

If the PTAB institutes a trial, it will issue a scheduling order with deadlines that ensure completion of the proceeding within that statutory deadline of 12 months after the institution date (this statutory deadline can move back if another party joins the IPR proceeding).

The PTAB ultimately issues a final written decision as to the patentability of each of the challenged claims. Absent certain circumstances (e.g., where a petitioner would not have Article III standing on appeal because they have not been sued for infringing the challenged patent), either party can appeal the final decision to the US Court of Appeals for the Federal Circuit.

IPR provides several advantages for challengers as compared to fighting validity only during litigation, including the following:

  • IPR proceedings take less time than litigation to reach a final disposition, usually 18 months or less from filing the petition.
  • IPR proceedings are substantially less expensive than litigation. For example, IPRs also provide for limited discovery only, which helps to reduce costs as compared to contesting validity during litigation, which has much more extensive discovery available.
  • IPR petitions may be filed at any time during the life of a patent, except for the nine months immediately following the issue date of a post–America Invents Act appeal.
  • Petitioners often request stays of any concurrent litigation in district court after filing an IPR petition.
  • The standard of proof for invalidating a patent in an IPR proceeding is a “preponderance of the evidence” (~51%) rather than “clear and convincing evidence” (>70%), thereby allowing the challenger a greater likelihood of success.

These advantages also come with certain risks. IPR estoppel is the main one. If challengers do not prevail, they may be estopped from raising grounds that were raised or could have reasonably been raised in the IPR in subsequent proceedings before the USPTO, federal courts, and the US International Trade Commission.

IPR proceedings became available in 2013 with the enactment of the America Invents Act.