How to Know If Your Products Infringe a Patent

Where do you start if you have been accused of patent infringement?

Disruptive and disconcerting – two of the most common emotions experienced by one accused of infringing a patent. Determining whether your products infringe a patent requires a methodical approach. A careful comparison of the patent claims and your accused products will help guide your strategy and next steps.

Need to know whether you can safely sell your products without infringing a patent? Call Vic at (949) 223-9623 or email to see how we can help you assess the risk of patent infringement in selling your products.

Are your products accused of infringing a design patent or utility patent?

A design patent will have the upper case “D” followed by a number. Here’s an example of a US design patent. What a design patent covers will be defined by the drawings. Therefore, a visual comparison with the design patent drawings will be required to see if your product looks substantially similar.

A utility patent will have a number of claims at the end of the written text. Whereas design patent infringement boils down to the drawings, determining utility patent infringement requires a careful reading of the written claims. It would be a costly mistake to judge the scope of a utility patent by simply looking at the figures.

How to Review Independent Claims

Start by identifying all the independent claims in the utility patent. Even if you can’t make sense of them, you should be aware of the number of independent claims that exist because your noninfringement analysis will require it.

If a particular patent has three independent claims, for example, the patent owner basically has three arrows in the quiver to shoot at your products. All they need is one arrow to hit. You must dodge each of these independent claims in order to avoid infringing the patent. You cannot assume you’re safe because your products avoid one independent claim when two other independent claims remain in the utility patent.

What will your patent attorney look for in analyzing noninfringement?

It goes without saying that you need an experienced patent attorney to help you navigate through the complex analysis of utility patent infringement. But, what will your patent attorney be looking for? The patent attorney will focus on any features recited in the independent claim, called “claim limitations,” that are arguably missing in your products.

Hopefully, we want to see multiple limitations in each independent claim missing from your products. The absence of multiple claim limitations in your products will help you form a stronger noninfringement argument.

What if you sold similar products before the patent was filed?

Another way to defend against a patent infringement claim is to argue that the patent is invalid. Invalidity refers to the patent claiming an invention that was not new and unique. In other words, preexisting products or literature already showed the patented invention before the patent application was filed.

To invalidate a patent, every element of the claim should be found in the prior product. Whereas noninfringement is about omitting certain claim limitations, invalidity is about including every claim limitation.

How to Sell Products That Do Not Infringe Patents

There may be a strategy for moving forward with selling products at a lower risk of patent infringement. Consider a Freedom-To-Operate search. Also known as an FTO search, this type of patent search will analyze live patents and determine your risk of infringement.

If a high risk of infringement exists with any particular patents, there might be a way to design around the claims by modifying your products. The key is knowing which product features to omit or change. Even if you do not believe your current products infringe a patent at issue, it may still be worthwhile to pursue certain product modifications that can reduce the risk of infringement without being overly burdensome.

An experienced patent attorney may want to study the file history of the asserted patent (e.g., Patent Office rejections and applicant’s responses) to identify the more important claim limitations to avoid, if possible.

Can your products infringe a patent if you have your own patent?

Yes, it is possible to infringe someone else’s patent even when you own a patent. Your own patent does not offer a defense against infringing other patents. However, you might be able to use your patent as a counterattack against competitors who are accusing you of infringement.

How useful was this post?

Click on a star to rate it!

Thank you for rating my post!

We want to do better.

Could you tell us what was missing in our post?

Innovation Capital Law Group
Ready to Slay Goliath?

What IP do you need?*

What IP do you need?*

(Check all that apply)

Your Name*

Your Name*

Your Email*

Your Email*

Your Phone Number

Your Phone Number

Design Patent Money-Back Guarantee
Get your design patent allowed or attorney's fees refunded. Call or email Vic to see if your design qualifies.

Not sure where to start? Email Vic at

Copyright © Vic Lin 2023