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Does My Product Infringe This Patent?

The Deceptively Simple Rule

Determining whether or not a product infringes a particular patent is simple in theory, but quite complicated in practice. To avoid infringing a patent all you have to do is avoid doing at least ONE thing (and its equivalent) in every claim of the patent. A patent claim is a one sentence description of the invention covered by the patent. A claim is typically a list of items, or elements of the core invention, and a description as to how they are related to one another. So to avoid infringement of a claim, you just have to look at all of the items in the claim and eliminate at least one of these items from your product. To avoid infringing the entire patent, you have to avoid infringement of EVERY claim in the patent. If the patent has twenty claims, and you only infringe one of those claims, the amount of money you will have to pay for the infringement is often the same as it would be had you infringed all twenty claims.

To determine infringement of a claim, you first have to examine the claim. For instance, assume a patent issued with claim 1 reading as follows:

A sitting device comprising:
a seat;
a leg coupled to the seat; and
a back coupled to the seat.

Applying the Rule

To avoid infringement of this patent claim, your product would have to NOT have one of those items. So if your product was a stool, and had no back at all, your stool would not infringe this patent claim. If your product had a seat and a back and four legs, your product would still infringe this patent claim, because your product does have at least “a” leg. Even if your product eliminates one of the elements of a patent claim, if the element your product has instead of the eliminated item performs substantially the same function, in substantially the same way, to yield substantially the same result, your product may still infringe the patent claim under the “Doctrine of Equivalents.” As you can see, the determination of infringement can get complicated very quickly. Once you determine that you do not infringe claim 1, you would then repeat the process for every other claim in the patent.

Never Make a Determination of Infringement Yourself

Unfortunately, determining whether a product infringes a patent claim is harder than it first appears. There is a reason patent infringement lawsuits take years to litigate and cost millions of dollars in attorney fees. The legal determination of what or what does not infringe a patent claim is an extremely complex process, involving the analysis of the claims, the specification, the drawings, the proceedings before the Patent and Trademark Office, and mountains of other patents and documents. It is imperative that no entrepreneur move forward on the assumption that their product does or does not infringe a patent without obtaining a formal written legal opinion from a patent lawyer well-versed in drafting patent infringement opinions.

Brett Trout

Posted in Patent Law.