United States: Challenges to Patent Validity

Last Updated: December 19 2014
Practice Guide by Brinks Gilson & Lione

The AIA introduced two new procedures that enable a third party to challenge the validity of an issued patent without having to go through court litigation.

These procedures are known as Post Grant Review and Inter Partes Review.

While Inter Partes Review may be sought against any issued patent, Post Grant Review may be sought only against a patent that issues under the auspices of the AIA; in other words, only a patent that has an effective filing date after March 16, 2013.

A brief synopsis of these new proceedings will give you an initial understanding of the benefits and disadvantages of each.

1. Post Grant Review. If a third party believes that a recently issued patent is invalid, the third party may file for Post Grant Review. To do so, they must file a petition within nine (9) months of the patent’s issuance.

There are many procedural and documentary aspects that must be set out in the petition, including:

• Identifying the real party of interest;

• Identifying the claims asserted as being invalid;

• Identifying the grounds supporting the challenge for each claim;

• Providing evidence to support the challenge; and

• Paying a fee to the USPTO.

The grounds that can be asserted in a Post Grant Review are broad. Thus, a petitioner may assert that the patent does not comply with the statutory subject matter, that the invention is not novel, that it is not unobvious, that it is not enabled, or that the written description requirement in the patent was not complied with. In other words, substantially any basis upon which a patent examiner could have rejected the application for patent is available for the petitioner’s assertion. However, one ground is not available, namely that the application did not comply with the best mode requirement (wherein the applicant describes the best way of carrying out the invention).

Evidence supporting the challenge can include prior art such as patents or printed publications, as well as affidavits and declarations of supporting facts and opinions. If the submitted evidence makes it “more likely than not” that at least one of the patent’s claims is un-patentable, or it presents a novel or unsettled legal question important to other patents/applications, Post Grant Review will be instituted.

Once instituted, the Review is conducted before the Patent Trial and Appeal Board (PTAB). During the proceeding, some limited discovery is available to the petitioner and the patentee. Additionally, the patentee has an opportunity to amend the patent, including cancelling the challenged claims and proposing a reasonable number of new claims. The amendment, however, is not permitted to broaden the patent’s claims.

If by a preponderance of the evidence a claim is determined to be invalid, it is stricken from the patent. If all claims are determined to be invalid, the entire patent is deemed invalid.

The fees associated with Post Grant Review are substantial and are intended to reflect some (but certainly not all) of the USPTO’s costs for conducting the proceeding. At the time of this writing, the total Post Grant Review fees (review request and post institution) are $35,800.

Post Grant Review proceedings are intended to be a quicker and cheaper adjudication of a patent’s asserted invalidity. The determinations under Post Grant Review are to be concluded within 12 months after the institution of the proceeding, which is far shorter than the timeline for court litigation. The PTAB’s determination is appealable directly to the CAFC.

There is a drawback, however, related to the legal principle “estoppel.” If a final decision is reached in a Post Grant Review proceeding, the petitioner will be “estopped” (prevented) from asserting a claim’s invalidity in subsequent litigation or International Trade Commission (ITC) proceedings on any ground that the petitioner raised--or reasonably could have raised--during the Review. If the parties settle prior to a final decision, however, no estoppel applies.

2. Inter Partes Review. In many respects, Inter Partes Review is similar to Post Grant Review. One difference is that if a third party believes that any issued patent is invalid, the third party may file for Inter Partes Review. However, a petition for Inter Partes Review cannot be filed until either the nine-month period for filing for Post Grant Review has expired or any instituted Post Grant Review proceeding has concluded.

The procedural and documentary requirements of Inter Partes Review generally mirror some of the Post Grant Review requirements, such as:

• Identifying the real party of interest;

• Identifying the claims asserted as being invalid;

• Identifying the grounds supporting the challenge for each claim;

• Providing evidence to support the challenge; and

• Paying a fee to the USPTO.

Grounds that can be asserted in an Inter Partes Review, however, are more restrictive, pertaining only to those grounds that could have been raised by an examiner under 35 U.S.C. 102 and 103—the novelty and obviousness provisions of the statute. Evidence supporting the challenge likewise can be in the form of prior art such as patents or printed publications, affidavits and declarations of supporting facts and opinions.

If, based on the submitted evidence, there is a “reasonable likelihood of success” with respect to at least one claim, the Inter Partes Review will be instituted. This standard of initial review is higher than the standard for Post Grant Review.

Once instituted, the PTAB conducts the proceedings, during which limited discovery is available and the patentee has an opportunity to amend the patent, including cancelling challenged claims and proposing new claims. Broadening claim amendments is not permitted.

If by a preponderance of the evidence it is determined that a claim or all of the claims are invalid, the invalid claim or entire patent is stricken or revoked.

The USPTO fees associated with Inter Partes Review are less than those for Post Grant Review, but are still substantial. At the time of this writing, the cumulative total of the review request and post institution is $27,200.

Determinations under Inter Partes Review are quick, within 12 months after the institution of the proceeding. Final determinations are similarly appealable to the CAFC.

Estoppel does also apply to final decisions in Inter Partes Review proceedings. Accordingly, a final decision will bar a petitioner from asserting a claim’s invalidity in a subsequent Inter Partes Review proceeding, civil litigation or ITC proceeding on any grounds that the petitioner raised, or reasonably could have raised. Estoppel does not apply if the parties settle prior to a final decision.

To find out more please access our IP Primer page.

This document is not intended to create an attorney-client relationship. You should not act or rely on any information in this document without first seeking legal advice. This material is intended for general information purposes only and does not constitute legal advice. If you have any specific questions on any legal matter, you should consult a professional legal services provider.

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USPTO is the federal agency for granting U.S. patents and registering trademarks.
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