Does the patent holder have to label the patented product? Is there any regulation on the method of labeling patented products? What happens if you don't label? What happens when a patent is falsely labeled? This guide answers these questions.

Under current U.S. law, patent owners are not required to mark the corresponding U.S. patent number on the patented product. However, there are many practical factors that should be considered in whether to apply for an annotated patent. For example, in different cases, the condition for obtaining damages at the pre-litigation stage is that the patentee has used the patent number to label the patented product as a notification to the potential infringer.

To comply with the labeling requirements, patent holders should use the term "patent" (or the abbreviation "Pat") along with the patent number for products protected by physical device or system type claims. If the product itself cannot be marked, it should be marked on the package. The licensee of the patentee should also label the products protected by the patent, which does not apply if neither the patentee nor his licensee sells the patented products, or if the patent covers only method or process claims.

According to the latest provisions of the America Invents Act (AIA), patentees can also satisfy the mark requirement by "adding the word 'Patent' or the abbreviation 'Pat' to it, along with a freely accessible announcement URL, and associating the patented product with the patent number in the announcement." If the URL points to a web page that lists the patented product and the associated patent number, this "virtual marking" allows the patent owner to provide a presumptive notification that the product is protected by the patent.

If a false label harms a party's competition, the party may bring a civil action under the America Invents Act.