Patent Marking: How to Mark Patented Products With Your Patent Number

How do you mark products with patent numbers?

The question is not if you should mark your patented products (of course you should!), but how. A little background on patent marking is in order. If you sell a product covered by product claims in your patent (as opposed to method claims), you will definitely want to mark your product properly with the patent number so that you can maximize monetary damages in enforcing your patent against infringing products and competitors.

To identify a single patent, you can simply mark the product and/or packaging with “PATENT [number]” or “PAT. [number]”. Alternatively, you can apply virtual patent marking as discussed below.

What if patented products are not marked by the patent owner?

Under the patent marking statute of 35 USC Section 287, a patent owner must provide notice of infringement in order to collect money damages. Failure to mark your products covered under your patents gives infringers an opportunity to argue that you are not entitled to any money damages prior to the time the infringers received actual notice of infringement.

Patent Marking: Actual Notice vs. Constructive Notice

Actual notice of infringement is accomplished by notifying the accused infringer of both the accused products and the asserted patents. This may be accomplished by, for example, sending a cease-and-desist letter or perhaps an enforcement letter containing a licensing offer. Serving the accused infringer with a patent infringement complaint would also constitute actual notice.

Constructive notice is achieved by the patent owner marking its patented products with the appropriate patent numbers. Constructive notice offers significant advantages to the patent owner in that accused infringers can no longer plead ignorance for failure to receive actual notice.

Constructive notice: What to mark

Before marking a product, a patent owner must initially consider which patents are at issue and which of its products are actually covered by the patent. Comparing the products to the patent drawings would work only for design patents, but not for utility patents. With utility patents, the products must be carefully analyzed with respect to the apparatus claims (non-method claims), particularly the independent claims. Does the product include all elements of at least one independent non-method claim in the utility patent? If so, a patent owner achieves constructive notice by applying to the product or packaging the word “patent” or the abbreviation “pat.” followed by the patent number(s). This is old school patent marking also known as “physical marking.” By doing so, a competitor cannot plead ignorance due to the lack of actual notice.

What is virtual patent marking?

What if the product is covered by multiple patents which are impracticable to mark on the product or packaging? Recent changes to the patent marking requirements under the AIA allows a patent owner to provide constructive notice by using a webpage to identify each patented product and the associated patent numbers. The patent owner must mark the product or packaging with “Patent” or “Pat.” followed by an Internet (URL) address that associates the patented product with the patent numbers.

Virtual patent marking provides a simplified and efficient process for patent owners to mark their patented products, particularly if a product is both patented and patent-pending. Instead of having to change the mold each time a new patent is granted, the patent owner can simply update the webpage while product mold and packaging printing remain unchanged.

Do patent marking requirements apply to method claim patents?

No, these marking requirements do not apply to patents containing only method claims. Nevertheless, it may bolster a patent owner’s rights to put patent numbers on products manufactured according to a patented process.

How to mark patent pending

If you have a pending US design or utility patent application that may cover your product, you may mark your product or packaging with “patent pending” or “pat. pending” or even simply “pat. pend.” While doing so might not necessarily give you any further legal rights, you might gain practical business advantages, including the potential discouragement or deferral of copycats by competitors. Marking your products with a patent pending notice could also provide consumers with the impression that your products are innovative.

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