United States: PTO Post-Grant Review: Patent Issuance Is Not End Of The Line

So, you find yourself a defendant in a patent infringement suit. Some patent holder has filed a lawsuit claiming that your company is infringing on their patented technology. The patent holder threatens to shut your business down with an injunction, obtain millions of dollars in damages, and make you pay hefty legal fees to defend yourself. So what do you do?

A typical defense would file counterclaims seeking to invalidate their patent, along with an argument that your technology does not infringe. But the court is not likely to resolve those claims until, at the earliest, a year or more into the litigation — and after the expenditure of significant legal fees. What's more, your success may well depend on how a non-patent-attorney judge construes the claim terms or how well you can convince a jury of laypeople of your arguments. Plus, because you'll be challenging an issued patent, you will face a higher burden of proof than the patent holder. But what other options do you have?

In a word, plenty. Although they are not necessarily cheap or simple, the U.S. Patent and Trademark Office offers a variety of administrative methods to challenge issued patents. These post-grant reviews come with better standards of review and are decided by seasoned, professional patent examiners. It may even be possible to stop the pending litigation while you take the fight to the Patent and Trademark Office. Post-grant reviews are powerful tools for patent infringement defendants. They come with their share of risks and drawbacks, but should never be ignored.

What is post-grant review?

Post-grant review refers to the assortment of administrative procedures offered by the U.S. Patent and Trademark Office for challenging the validity of issued patents. These proceedings allow third parties (or patent holders themselves) to effectively reopen patent examination to challenge and possibly invalidate patents that never should have issued, to evaluate issued patents in light of newly discovered prior art, or even to amend current patent claims to better evade prior art. Currently, there are four types of post-grant review offered by the Patent and Trademark Office:

  1. Ex parte reexamination
  2. Post-grant review
  3. Inter partes review'
  4. Covered business method patent review

Each of these proceedings have their own nuances, offer their own advantages, and come with their own unique risks. In this post, we'll take a look at the first two methods; in tomorrow's post, we'll cover the last two.

Ex parte reexamination

Ex parte reexamination is the oldest of the post-grant review possibilities and dates back to 1981. As the name makes clear, ex parte reexamination is an ex parte process, meaning that the challenge is conducted largely without the input of the challenger and involves only the patent holder and the Patent Office. The process begins with a challenger — possibly a company targeted by an infringement suit — requesting an ex parte reexamination.

In this request, the challenger submits published prior art (no declarations or testimony, only patents or publications) along with arguments of how the prior art invalidates at least one claim in the issued patent. The challenger must also pay the $12,000 filing fee. If the Patent Office determines that a substantial new question of patentability has been raised with respect to at least one patent claim, it opens the reexamination. At this point, the challenger's role in the reexamination is complete. From that point on, all activity in the reexamination takes place between the patent holder and the Patent Office as they argue over the validity of the claims in the patent at issue. If the challenge to the patent is ultimately unsuccessful, the challenger is free to raise the same invalidity defenses during the course of later or pending litigation.

Post-grant review

This is a new process created by the America Invents Act. This procedure can be used in the first nine months after the issuance of a patent and only applies to patents that issue from applications filed after March 16, 2013 — meaning that is highly unlikely that this process is available yet for parties that want to challenge a patent.

Still, assuming you have an eligible patent at issue, during this limited window nine months after issuance, any third party can file a petition seeking the review based on any available invalidity defense (including written description, enablement, indefiniteness) and by paying the accompanying filing fee of $12,000. After filing the petition, the patent holder may file a preliminary response arguing its side of things, but is not required to do so.

If the challenger can show that it is more likely than not that at least one of the patent's claims are unpatentable or that the petition raises a novel or unsettled legal question that is important to patent law, the Patent Office will trigger a post-grant review. At this point, the challenger must pay an additional $18,000 to keep the post-grant review going.

From this point on, unlike in ex parte reexaminations, the challenger, patent holder, and the patent office will all argue about the validity of the challenged patent. It is contemplated that both the challenger and patent holder will be allowed to take limited discovery directly related to factual assertions advanced by either party during the proceeding, but these procedures have not yet been finalized. If the post-grant review is ultimately unsuccessful at the Patent Office, the challenger will be estopped from raising any of the arguments it raised, or reasonably could have raised, in the post-grant review. This effectively means that if a post-grant review is underway, it will be the only venue for challenging the validity of the patent for the challenger. Because of this, and the fact that the post-grant review is statutorily required to be completed within one year, courts are more willing to stay pending litigation involving a challenged patent to allow the invalidity challenge to be handled by the Patent Office.

Look to our next post for a summary of the last two avenues for administrative challenges to issued patents.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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