Top 3 Ways to Defend Patent Infringement Claims

How do you defend a patent infringement claim?

Accusations of patent infringement should be taken seriously. Whether they are asserted in the form of cease-and-desist letter or an Amazon patent violation, an accused infringer must gauge the seriousness of the problem. Do the accused products actually infringe the asserted patent? Are the patent claims invalid? Let’s explore the top ways to defend against patent infringement claims.

Need an effective patent infringement defense? Call US patent attorney Vic Lin at 949-223-9623 or email to explore how we can help you defend against a patent infringement claim.

#1 Patent Infringement Defense: How to Argue Noninfringement

This is perhaps the most common defense to patent infringement. To argue noninfringement is to show that your product is missing a required claimed feature. This will likely involve a noninfringement review by a patent attorney with experience in patent infringement litigation.

Utility patents are generally more complicated to review than design patents. Avoiding infringement of a utility patent requires that each independent claim be analyzed, and there might be several.

Noninfringement of a design patent boils down to the appearance. There is only one claim in a design patent, and it essentially consists of the drawings.

How do you use noninfringement arguments? If you are involved in an Amazon patent violation, you can hire a patent attorney to submit an appeal. Avoid the urge to hire a lawyer solely based on fees. Your goal is to win, not spend less money in a losing effort.

#2 Patent Infringement Defense: How to Argue Invalid Patent

Invalidity is quite different from noninfringement. To invalidate a patent, you are not arguing about the absence of claim limitations in your product. Instead, you are arguing that the patent is invalid because it fails to claim something new and unique. In other words, you have prior art to show that the patent should not have been granted in the first place.

Patent invalidity requires a completely different type of analysis than that of infringement. Instead of finding at least one missing claim limitation as you would with noninfringement, you need to find all the claim limitations in the prior art. For example, if Claim 1 recites ABC, you need to find all three features – A, B and C – in the prior art in order to invalidate that claim.

Astute observers will recognize that noninfringement is specific whereas invalidity is general. In other words, noninfringement arguments are specific to each particular product. Product A might have noninfringement arguments that do not apply to Product B.

Invalidity, on the other hand, would make the patent impotent against the entire competition. Therefore, a patent owner has potentially more to lose with invalidity than with noninfringement.

So how do you use an invalidity defense? You can file a request for reexamination with the USPTO. If the request for an ex parte reexamination is granted, the remaining proceeding will be conducted between the patent owner and the USPTO. The requestor does not get to participate throughout the reexamination proceeding.

The outcome of a patent reexamination may vary. Claims in the reexamined patent may be canceled, amended or unchanged. During the reexamination process, the patent owner will have the opportunity to make arguments and claim amendments with respect to the prior art.

Another way to use the invalidity defense is to send the patent owner a letter with the invalidating prior art, and request that the patent owner leave you alone. Since the patent owner is motivated to keep their patent valid against other competitors, they might choose not to enforce the patent against you any further for fear of losing their patent rights.

For Amazon neutral patent evaluations such as APEX, keep in mind that invalidity is not an available defense unless it is the accused seller’s own prior sales. Here are some FAQs on Amazon IP policies.

#3 Option: Modify Your Product

What are your options if you cannot argue noninfringement or invalidity? Consider ways to design around the patent. This option is more of a risk mitigation strategy than a defense. In fact, you can consider this option even if you have arguments for noninfringement or invalidity.

A patent attorney with infringement experience may be able to guide you on what modifications would be more worthwhile to pursue. To do so, a deeper dive into the file history (aka “prosecution history”) of the patent may be required. You will need to know what prior art references were cited by the patent examiner and how the applicant responded to those claim rejections.

Any claim amendments and accompanying arguments made by the patent applicant may help to provide a roadmap for avoiding infringement of the claims that were ultimately granted.

What are your patent defense options when a lot of money is at stake?

Some sellers may be losing six figures of sales per month due to patent infringement accusations. If you believe you have strong arguments for defending against patent infringement, talk to a patent attorney with infringement litigation experience about your options.

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