Labeling your product with information about patent(s) that cover that product is called "patent marking" and is one way to inform the public about your IP rights. While under U.S. law you aren't required to mark your products, not doing so may limit the amount of damages you can recover if someone infringes your patent(s).

In particular, if you are successful in an infringement lawsuit, you can recover damages from the infringer for up to six years of infringement prior to the date of the lawsuit—but only if the infringer was actually aware of your patent or if you marked your product. In most cases, these past damages are available because the patent holder marked the product, rather than actual knowledge by an infringer.

If your patent only covers a method, rather than a product, then marking is not required—since there is nothing tangible to mark. This might apply, for example, if the patented invention covers a service that cannot be embodied in something physical. If you aren't sure whether you can or should mark your product, contact your Fenwick & West patent attorney, who would be happy to discuss the options with you.

And, if you aren't manufacturing any products or providing any services covered by your patent, that's okay—you can still recover damages and you aren't required to mark anything.

How to Mark?

You can mark a product by printing "Patent" or the abbreviation "Pat." together with either the patent number or a free-to-access web address of a page that associates this product with the patent number ("virtual marking").

Sometimes an article cannot be marked—for example, because it relates to something going on inside a computer, or because the product itself is too small. In that case, you can mark the packaging that accompanies the product.

Whether you mark the product or its packaging, one advantage of virtual marking is that the product or packaging can remain the same, even as your portfolio changes over time. You can have a single web page that lists the patents associated with each product, or you can have a different web page for each product. Because how you mark the product or its packaging need not change, it's important to keep the web page up to date. For example, you should update the web page as products are reconfigured and as patents issue, expire, or are limited or found invalid by a court. Also consider making the product and patent information easy to locate on the web page so that a user can find the relevant information without significant effort.

To benefit from the legal provisions related to marking, the marking must be substantial and continuous—that is, you should mark substantially all of the products manufactured, not just some of them; and the marking should be continuous over the life of the product or the patent (whichever is shorter). This requirement applies to virtual marking too, so you should maintain records of the web page, including records showing that the web page was consistently operational.

A product may only be marked with patents that cover the product. Periodically review your product and active patent portfolio to make sure the marked product is actually covered by the specific language of your active patent claims and to remove patents that no longer cover the product. Marking a product with inapplicable patents can create liability for false marking.

Finally, if you license your patent to another entity, you should take reasonable steps to ensure that the licensee is marking any products they sell as well.

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.