How to challenge patents (with lower costs)

What are less expensive ways to challenge patents?

As a patent attorney, it’s my job to protect innovation. Innovation is wonderful, but so is fair competition. Competition, in general, is good for consumers because it raises the level of quality and lowers prices. Fair competition respects the valid IP rights of innovators. Just as there always seems to be two sides to an argument, there will often be a reasonable counterpoint to a claim of patent infringement. There are times when companies engaged in fair competition must decide if it makes business sense to challenge patents.

If you are on the receiving end of a cease-and-desist letter or some assertion of infringement, it helps to know your options when you feel that a particular patent should not apply to your products.

A well thought-out reply letter

One fairly inexpensive approach is a reply letter with detailed reasons why you believe the patent is invalid or not infringed. Keep in mind that noninfringement is different than invalidity, so it would be best to use an experienced US patent attorney to formulate the precise technical arguments.

It’s a strategic decision on whether or not to include claim charts in your letter. At a minimum, your letter should contain a sufficiently detailed analysis that would give the patent owner pause. Pithy conclusory statements of “we don’t infringe” or “your patent is invalid” will likely accomplish little. Instead, a thorough explanation of the reasons why their patent should not prevent you from competing will likely make the patent owner (and their patent attorney) think twice before enforcing their patent any further.

Imagine if you were the patent owner that sent out a cease-and-desist letter. What would make a bigger impact, a curt reply without any explanations or an articulate response with intelligent arguments? How would a reasonable patent owner respond to these different types of replies? You have to assume the patent owner will act reasonably; otherwise, all bets are off since it won’t make much difference what you do when the other side is unreasonable.

How is “ex parte” different than “inter partes“?

When it comes to challenging patents before the USPTO, proceedings can be either “ex parte” or “inter partes.” “Inter partes” means between two parties, and thus refers to a two-sided adversarial case. For example, an Inter Partes Review (IPR) involves a challenge of a patent brought before the PTAB and litigated between the challenger and the patent owner.

Ex parte, on the other hand, means one-sided or a single party. For example, the patent filing process is ex parte because it involves only the applicant in dealing with the patent examiner. Third parties generally do not get to participate in the patent application process.

How to challenge patents by requesting an ex parte reexamination

An ex parte reexamination of an issued patent involves only the patent owner and the Patent Office. A third party challenger may file the initial request for reexamination. If a Patent Owner’s Statement is filed, a third party requestor may also submit an optional reply. Beyond that, the third party requestor does not get to participate in the ongoing review of the validity of the patent. If the patent owner were to argue that its claims are still valid over certain prior art, for example, the challenger cannot respond with counterarguments as to why the claims are invalid.

There are three possible outcomes for each claim in a reexamined patent:

  1. confirmed (unchanged);
  2. canceled; or
  3. changed.

USPTO statistics for 2019 show that 91% of requests for reexamination were granted, meaning that the successful requests satisfied the requirement of showing a substantial new question of patentability (SNQ). In reexamination proceedings where the request was filed by a third party (i.e., not the patent owner or the Patent Office), 79% of claims were canceled or changed.

So if you are thinking of requesting reexamination of someone else’s patent, you have over 92% chance of the request being granted and, once granted, an almost 80% of seeing claims canceled or amended. So, a third party requestor has a roughly 73% chance of success in getting patent claims canceled or changed as a result of reexamination.

How much does ex parte reexamination cost?

For a small entity (e.g., business with fewer than 500 employees), the USPTO fee for requesting reexamination is $6,300. However, a streamlined reexamination costs half the price at $3,150 if the request has 40 or less pages and meets other format requirements.

Our firm can provide flat rate estimates for filing an ex parte reexamination request. Attorney’s fees at our firm typically start at $15,000, depending upon the number of claims and prior art references. A higher number of claims will require more work and more pages, which may exceed the 40-page limit of the cheaper streamlined reexamination request.

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