What Is Ex Parte Reexamination?

Ex parte reexamination is a tool that allows a patent owner or a third party to lodge a request for the United States Patent Office (USPTO) to reexamine an already-granted patent based on other patents and publications that they bring to the USPTO's attention.

An ex parte reexamination can be requested at any time during the enforceability of the patent. The requester needs to establish that the prior art creates a substantial and new question of patentability (SNQ). The reexamination is conducted in front of a panel of three experienced examiners within a specialized unit of the USPTO called the central reexamination unit (CRU).

Ex parte reexamination proceedings involve only the patent owner and the USPTO. After the request is filed, the third-party requester is removed from further involvement unless the patent owner files a statement seeking to rebut their assertions.

Requests for continued examination (RCEs) are not available in ex parte reexamination proceedings. No legal estoppel is created by an ex parte reexamination proceeding.

Ex parte reexamination has been available since 1981 and continues to be available under the America Invents Act (AIA).

Substantial New Question of Patentability

A substantial new question (SNQ) is a way to reduce harassment of patent owners by forcing the third-party requester to show that the questions against the patent have enough weight.

The SNQ needs to originate from a prior patent or a printed publication. An SNQ is not a proposed ground for rejecting a patent. Not all previously considered references, such as old art, or unconsidered references, such as new art, can raise an SNQ. Old art can be used to support an SNQ only if it is shown in a new light. New art can be used to support an SNQ only if the technological teaching relied upon in the art has not already been considered by the office in earlier reviews of the patent.

Timeline for Ex Parte Reexamination

The USPTO aims to have ex parte reexamination completed in a timeline of fewer than two years.

  • Month 0 - A request for an ex parte reexamination is made.
  • Month 3 - The central reexamination unit needs to decide whether they will grant or deny the request within three months of the request being made.
  • Month 4 - If the request is denied, the requester has one month to petition for reconsideration.
  • Month 5 - If the request is granted, the patent owner has two months to file a statement responding to the questions being posed and to amend their claim if they wish to. Filing a statement is optional and it usually isn't done.
  • Month 7 - If the patent owner does decide to file a statement, the requester has two months to file a reply statement if they wish to.
  • Months 6-8 - A First Action needs to be issued within one month from the expiration of the patent owner's 2-month window of filing a statement.
  • Months 8-12 - The patent owner then has two months to respond to the First Action. This can be shortened to one month if there are pending proceedings like litigation or reissue. Extensions may be given if sufficient cause is shown. The patent owner can also ask for an interview during this time.
  • Months 12-24 - During the second year, several things can take place:
    • The second Office Action in the reexamination proceedings is made final.
    • The CRU has an internal goal of issuing a Final Office Action within two years from the filing date of the request.
    • The period for response to a final rejection is usually two months, but it can be shortened to one month. A response after the final rejection does not automatically get entered or filed. If the CRU does decide to file it, the time period is automatically extended by one month.
    • If the response does not place all claims in a condition where they are patentable, the examiner will issue an advisory action providing the patent owner enough time to consider the action and either file a notice of appeal or a second response that clearly places all claims in conditions where they are patentable.
    • The patent owner can appeal any decision that changes the status of their patent to either the USPTO or in court.
    • Upon conclusion of the reexamination proceeding, the examiner will issue a Notice of Intent to Issue Ex Parte Reexamination Certificate (NIRC), which sets forth the status for each claim that was made.
  • Month 25.7 (average) - The reexamination is issued.

Benefits of Ex Parte Reexamination

Ex parte reexamination proceedings can offer three main benefits.

  • A reexamination proceeding can settle validity disputes quicker and cheaper than litigation.
  • Reexamination proceedings allow courts to refer patent validity questions to the expertise of the Patent Office.
  • A reexamination proceeding reinforces investor confidence in the certainty of patent rights by giving the USPTO an opportunity to review doubtful patents.

In addition to these overall benefits, ex parte reexamination also benefits the third-party requester in several ways:

  • Anyone can file a request for an ex parte reexamination.
  • There are no jurisdic­tion or other requirements to be a third-party requester.
  • Third-party requesters can remain anonymous.
  • Once a reexamination is requested, it continues until a reexamination certificate is issued. It can't be withdrawn.
  • As soon as the reexamination is ordered, the patent in question no longer has a presumption of validity.
  • During reexamination, claims are given their broadest reasonable interpretation.
  • The patent owner's amendments and arguments can create prosecution history estoppel.
  • A Request for reexamination can be filed up to the six additional years of enforceability of the patent with respect to a patent infringement after the patent has expired.
  • A reissue application can't be filed after the term of the patent has expired.
  • If there are additional requests for reexamination, they can be filed on additional substantial new ques­tions of patentability of the patent claims and merged with the current reexamination proceeding.
  • Claim amendments made during the proceedings can provide intervening rights to the infringer.

Drawbacks of Ex Parte Reexamination

Ex parte reexamination can have several drawbacks for the third-party requester that should be clearly understood and considered before filing for an ex parte examination.

  • Third-party requesters cannot take part in the proceedings once the initial request has been made.
  • Third-party requesters can't appeal any decisions that the patent claims are patentable prior to issuance of a reexamination certificate.
  • A third-party requester can't stop the issuance of a reexamination certificate that deter­mines certain claims patentable.
  • A third-party requester can't stop a patent owner from amending the existing claims or adding claims of the same scope to make their claim stronger.
  • The third-party requester can't stop a broadened reissue from being filed by the patent owner and having the ex parte reexamination proceeding merge with the new application.
  • Third-party requesters can't stop ex parte interviews from the examiner and patent owner, nor can they take part in the interviews.
  • A reexamination certificate may be issued, meaning that the original patent will have gone through two USPTO decisions. This will make that patent even more valid.

Ex Parte Reexamination Versus Inter Partes Reexamination

The post-grant patent world changed forever on September 16th, 2012. On this date, inter partes patent reexamination was discontinued and replaced with the Inter Partes Review (IPR) proceeding. IPR proceedings can be used to challenge any patent, regardless of vintage. The USPTO fee to request an ex parte patent reexamination then rose from $2,520 to $17,750.

  • Both ex parte and inter partes reexamination submits a patent to an examination process similar to the original process it went through when the patent was issued.
  • Ex parte reexamination can be requested by anyone at any time, but only the patent owner participates in the reexamination proceeding.
  • In inter partes reexamination, the third-party requester can actually take part in the reexamination proceedings.
  • Unlike ex parte reexaminations, inter partes reexamination requests are not anonymous. The third-party requester has to be identified. Inter partes reexamination requests can only be filed against patents issued from an application filed in the United States on or after November 29, 1999.
  • In an inter partes reexamination, the third-party requester is allowed to file comments in response to submissions made by the patent owner, and they can appeal the USPTO's decisions.
  • The estoppels created because of an inter partes reexamination and any further litigation are among the most important differences between the two.
  • Estoppels in an inter partes reexamination flow two ways:
    • From the inter partes reexamination to the civil action.
    • From the civil action to the inter partes reexamination.
  • If the technology is simple and the prior art is substantial, the ex parte review will allow the challenge to move forward with a minimum of investment in attorney and USPTO fees.
  • IPR is better than ex parte patent reexamination in terms of ability to participate and demonstrate unpatentability, but the cost of such participation is substantial.
  • In order to be granted a request for inter partes reexamination, you need to show that there is a reasonable likelihood that you will win with respect to at least one claim.

Required Elements of a Reexamination Request

An ex parte reexamination request needs to have:

  • A statement that points out each substantial and new question being raised.
  • A detailed explanation that demonstrates the connection between the cited patents to every claim for which reexamination is requested.
  • A copy of every patent or printed publication where there are substantial and new questions.
  • A copy of the patent for which the reexamination is requested.
  • Certification that a copy of the request has been served on the patent owner.
  • The fee payment.

An inter partes reexamination request needs to contain:

  • Identification of the patent in question and every claim for which reexamination isi requested.
  • Citation of the patents and printed publications for the substantial and new questions.
  • A statement that points out each substantial and new question.
  • A copy of every patent or printed publication relied upon in the substantial and new questions.
  • A copy of the patent that is being requested for reexamination.
  • Certification from the requester that a copy of the request has been served to the patent owner.
  • Certification by the requester that the estoppel provisions do not prohibit reexamination.
  • A statement identifying the third-party requester.

Frequently Asked Questions

  • What is the difference between a reexamination and a reissue?

Some of the most important differences between a reexamination and a reissue are:

  • The USPTO can regain jurisdiction over an issued patent that is up for reissue when "the patent is, through error without a deceptive intention, deemed wholly or partly inoperative or invalid, by reason of a defective specification or drawing, or by reason of the patentee claiming more or less than he had a right to claim in the patent…."
  • A reexamination can't be filed to correct a specification, a priority claim, or drawings.
  • A reissue proceeding can only be initiated by the patent owner while a reexamination is initiated by either the patent owner or a third party.
  • Claims involved in a reexamination proceeding can not be broadened in scope.
  • Claims involved in a reissue can be enlarged in scope if the reissue was filed within two years from the time the original patent was granted.
  • A reissue cannot add any subject matter disclaimed during the original prosecution.
  • Are reexaminations becoming more common?

Yes, they are. Ex parte reexaminations are much more common than inter partes reexaminations. In 2008, 680 ex parte reexaminations were filed. This number has increased steadily since then. In 2008, 168 inter partes reexaminations were filed. This number has increased even more dramatically since then.

  • What percentage of reexamination applications have their claims confirmed?

Twenty-five percent of ex parte reexaminations have resulted in confirmation of all claims made. Eleven percent of ex parte reexaminations have resulted in all the claims being canceled. The other 64 percent of ex parte reexaminations resulted in some change in the claims.

  • Is the burden of proof in a reexamination identical to normal prosecution?

Yes, both the CRU and the USPTO use a "preponderance of the evidence" standard for deciding patentability. This means that the Examiner should reject a claim if it is more likely than not that the claim is unpatentable.

  • Is it possible to stay a pending reexamination before the USPTO?

Technically, stays are available in reexaminations, but it can be difficult. The rules give the patent owner the ability to ask for a stay, but the USPTO usually does not grant such requests due to the statutory mandate to handle reexaminations with special  dispatch.

  • Can a District Court judge contact the Central Reexamination Unit at the USPTO?

Judges deciding a motion to stay or presiding over a litigation about a pending reexamination can consider contacting the CRU. The  Office of Patent Legal Administration (OPLA) has a phone number where questions dealing with "Reexamination and Reissue Legal  and Policy Guidance" can be answered.

  • How long does it take for the PTO to grant or deny a request? 

The CRU has an internal goal of issuing all final office actions or an Action Closing Prosecution within two years of the filing date. Their ability to stick to this metric depends greatly on the type of patent that you are filing an action against. The chemical and biological group has no backlog. Nearly 90 percent of the mechanical reexaminations have achieved this goal. Only 70 percent of the electrical, software, and business method reexaminations have received a final action by the end of the second year.

There are no reliable statistics on how long a reexamination case takes once granted. A patent undergoing reexamination is still enforceable until ideemed otherwise. 

The USPTO takes the position that a settlement agreement is not a final decision on whether a patent is valid or not and therefore will not terminate the reexamination proceeding. They will continue until they have decided whether the patent is valid or not.

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