Ex Parte Reexamination


Ex Parte Reexamination

Issued patents have a presumption of validity, but this doesn’t mean they can’t be challenged. Ex parte reexamination is one of the most utilized methods of doing this, and it’s both cheaper and quicker than patent litigation. This offers an easy way for third parties to contest a patent’s legitimacy, and although it may be a hassle for the patent owner, the patent may become even stronger after the fact.

Patent Reexamination

Once a patent has been approved by the U.S. Patent and Trademark Office (USPTO), the patent owner has exclusive rights over their invention. When someone files a patent reexamination request, though, there’s a risk that the owner could lose these rights. The goal of an ex parte reexamination is to present evidence which could invalidate a patent or a specific claim.

The ex parte reexamination process allows third parties or a patent owner to file a request.  For a reexamination to be considered, a substantial and new question of patentability must be raised. This will come in the form of prior art from publications or former patents.

Consider the following examples of prior art:

  • Industry journals detailing a mechanism.
  • Trade show presentations of a new product.
  • Prior patent applications.
  • Proof of an invention’s previous commercial use.
  • Products being for sale on the market prior to the patent filing.

Each of these instances must have occurred before a patent’s effective filing date for an issue to be raised. This list is not exhaustive. Any evidence that shows an invention was publicly available or known prior to the effective filing date constitutes prior art.

An ex parte patent reexamination can be filed during any point of enforceability.  Since reexaminations can be filed during patent litigation, their potential as an evidentiary tools is high.

There are several additional benefits of ex parte reexaminations:

  • Disputes over validity can be settled outside of the courtroom – saving time and money for both parties.
  • Investor confidence is reinforced due to the availability of a mechanism to review questionable patents.
  • Courts that may not have technical experience in certain areas can defer to the USPTO’s expertise.
  • Three USPTO examining patent attorneys – rather than one – decide patentability.

While the benefits of an ex parte patent reexamination are numerous, there are also drawbacks to the approach. Once the third-party filer submits their request, for instance, their involvement is over. The owner of a patent is allowed to file a rebuttal – which in turn will lead to a response from the complainant– but the third party will not take part in the hearing before the Central Reexamination Unit (CRU).

When the Central Reexamination Unit decides that a substantial and new question of patentability is legitimate, they will grant the ex parte patent reexamination. Their goal is to finish all these cases within a two-year period. If the patent survives this process, the patent owner will receive a reexamination certificate. This will provide an even higher degree of validity in courts since the patent will have gone through the USPTO twice.

You can expect the following timeline for ex parte reexaminations:

  • Month 3: The CRU has three months to decide whether to grant a reexamination.
  • Months 4-7: Requesters can submit a petition for reconsideration within a month of their request being denied. If the reexamination is initially approved, a statement can be filed by the patent owner which responds to the newly raised questions. If they go this route, the requester can file a response within two months.
  • Months 6-8: Within a month of the patent owner’s expiration for filing a statement, the CRU must issue a First Action.
  • Months 8-12: A response must be filed by the patent owner within two months of receiving the First Action. Interviews can be requested, and extensions may be granted in certain circumstances. This two-month period can be shortened if another proceeding – such as a reissue or patent litigation – is ongoing.
  • Second Year: Second Office Actions may be issued and finalized. Patent owners have 1-2 months to respond to Final Office Actions. If the claims in their patent are not corrected, they’ll receive an advisory action that allows them to submit a second response or appeal. When the proceeding has concluded, a Notice of Intent to Issue a Ex Parte Reexamination Certificate is issued.

The average time before the reexamination is issued is just short of 26 months. Patent owners can appeal the decision through the USPTO or federal courts. If their registration is invalidated, they immediately lose all exclusive rights. This can be a significant development in any pending litigation since – if a patent is invalid – no alleged violations could have occurred.

Patent Reexamination Search

When an ex parte reexamination request is approved, it becomes part of the public domain. This allows patent owners and other interested parties to conduct patent reexamination searches via the USPTO website. The Public Patent Application Information Retrieval (PAIR) system is utilized to conduct these searches.

Public PAIR is accessible by anyone, but it only provides information on published applications and registered patents. The Private PAIR system grants access to any application – whatever its publication status – but is only accessible by authorized individuals. These includes agents, patent attorneys and those working at their behest.

You can conduct a patent reexamination search using any of the following data:

  • Patent Number.
  • Application Number.
  • Control Number.
  • Publication Number.
  • PCT Number (i.e. International Application Number).
  • International Design Registration Number.

Users can utilize this tool to determine if a reexamination request was filed for a certain patent or view the files for known proceedings. Any submission could take several days to update in the system, so it’s important to check back often after a request has been filed. Since the filer of an ex parte reexamination can remain anonymous if they choose, this would be their only method of tracking progress.

Patent Trial and Appeal Board

When someone doesn’t agree with a USPTO ruling, they can file patent litigation in federal court. Since this often becomes expensive and time-consuming, though, the decision to utilize the Patent Trial and Appeal Board (PTAB) is a frequent one. Although it’s the CRU that decides ex parte reexamination requests, the PTAB handles all appeals of these decisions within the USPTO.

The pendency of these appeals typically hovers right around 15 months, so the process that began with reexamination could end up lasting over three years.  The PTAB database allows users to track trials, appeals, decisions and more.

Going through the PTAB process has a variety of benefits:

  • Saves time and money over patent litigation.
  • High-quality rulings (Federal Courts only reverse about 7 percent of their decisions).
  • PTAB can consider settlements (ex parte reexaminations will not).
  • Discovery is limited in scope. This reduces costs even further.
  • Decisions made by technically trained judges rather than an unknowledgeable jury.

While the Patent Trial and Appeal Board is very important for ex parte reexamination appeals, this isn’t their only job. They also directly handle other forms of post-grant proceedings. These include inter partes reviews (IPR) and post-grant reviews (PGR). Rather than simply handling the appeals for these cases, the PTAB is the USPTO branch that deals with these proceedings from the start.

Post-Grant Review

Another way of challenging a patent’s validity is through a post-grant review. Unlike an ex parte reexamination, all involved parties are identified in a post grant review. This means that the requestor cannot remain anonymous, but it also gives them the ability to present their case directly to the PTAB. Only third parties – not the patent owner themselves – may initiate a post-grant review.

After a PGR request is filed, a patent owner has three months in which to file their preliminary response. Following this response, the PTAB has an additional three months to decide whether to move forward with the trial. If no preliminary response is submitted by the patent owner, though, this timeline can be expedited. Compared to ex parte reexaminations, PGRs also have several more grounds for filing:

  • Prior art invalidity.
  • Failure to meet novelty, usefulness and non-obvious requirements.
  • Lack of enablement.
  • Public use or disclosures.
  • Anticipation.
  • Written description.
  • Subject matter isn’t patentable.

This list is not exhaustive, but it showcases the wider range of options for having a patent invalidated. To be eligible for this remedy, however, third parties must file their request within nine months of a patent’s issue or reissue. This timeframe may help explain why only 2 percent of the petitions filed with the PTAB fall under this category.

Unlike the substantial and new questions required for an ex parte reexamination, the threshold required by the PTAB for post-grant reviews is only that the petitioner is “more likely than not” to succeed. Their submission can focus on multiple claims within a patent registration, but as long as the filer is likelier to succeed than fail in invalidating even one, a PGR can move forward.

There are several other differences between post-grant reviews and ex parte reexaminations:

  • Estoppel is created: Patent can’t later be challenged based on grounds that were raised or may have reasonably been raised.
  • Concurrent litigation: The American Invents Act set certain limitations on PGRs occurring concurrently with litigation.
  • Court of Appeals restriction: Appeals can only be heard through the Federal Circuit Court of Appeals. Ex parte reexaminations can also appeal through District Court.
  • Settlements: The PTAB may allow parties to settle their issue prior to completion of proceedings.

Post-grant reviews also hold several advantages over patent infringement litigation. The evidentiary standard, for instance, is much lower than in courts. There’s also no presumption of validity before the PTAB, so the parties are on equal ground. Additionally, the PTAB uses the “broadest reasonable interpretation” of a patent claim – while courts often use claim construction.

While post-grant reviews have a variety of benefits over litigation and other proceedings, they still have limitations. This is why the bulk of proceedings before the PTAB fall under different categories. While a PGR can succeed in canceling certain claims – or the entirety of a patent – an inter partes review may be more appropriate.

Inter Partes Review

The PTAB also allows third parties to challenge the validity of a patent through inter partes review (IPR). The requester cannot remain anonymous during the process, but this means they’re able to present their case directly to the USPTO. If you’re eligible to file a post-grant review, you cannot use the IPR procedure until the nine-month deadline has passed.

For the PTAB to accept an inter partes review, it must be shown that there’s a “reasonable likelihood that the petitioner would prevail” against at least one of the challenged claims. While a post grant review can only be submitted against patents with effective filing dates on or after March 16, 2013, an IPR can be filed on any patent. Unfortunately, only claims of lack of novelty or obvious serve as grounds for filing.

There are a variety of differences between inter partes review and ex part reexamination:

  • Who can file: Only third parties – not the patent owner – can submit an IPR.
  • Estoppel created: Parties cannot challenge patent based on grounds that were raised or could’ve reasonably been raised during the proceeding.
  • Concurrent litigation: Challengers who file lawsuits based on a patent’s validity cannot file an IPR. For other cases of patent litigation, petitions must be filed within 12 months of district court filing.
  • Court of Appeals restriction: Appeals must be heard at the Federal Circuit Court of Appeal for inter partes reviews. The District Court isn’t an option.
  • Settlements: The PTAB can accept settlements between the two involved parties.

About 92 percent of the trials handled by the PTAB are inter partes reviews.  At the conclusion of an IPR, it’s possible that the outcome will extend outside of “claims confirmed” or “claims cancelled.” In fact, the majority of cases end with the owner simply making changes to their claims.

You can perform a patent reexamination search linked to inter partes reviews and post-grant reviews via the USPTO End to End (E2E) database. This is a free tool to utilize and allows users to find current proceedings or discover whether a patent has gone through PTAB hearings previously. As with other reexaminations, a patent that survives an IPR will carry additional weight in court.

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If you are considering filing an ex parte reexamination, or if one has been filed against you, please contact us today for a free consultation.


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