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Intellectual Property

Patent Marking

By Art O’Dea

Patents are an extremely useful and valuable tool to support business development, new product introduction, and competitive positioning in the market. However, as with any of the tools that are carried, they need to be cared for and handled properly. One of the associated tasks of managing a portfolio of patents is to ensure that your patented products are properly marked.

Patent Marking is governed by 35 U.S. Code § 287. The statute generally permits patent holders to “give notice to the public” that an article made or sold within the US is patented, and if properly marked, an infringer can be held liable for damages during a period prior to actual knowledge of such infringement. If the public can identify an article as patented, innocent infringement can be avoided. Generally speaking, the incentive for effective marking of patented products is maximum recovery in an infringement action.

It is important to note that the statute does not require that products be marked. However, in the event of a failure to mark, pre-litigation damages do not accrue. There is no time limit by which marking must begin, but it is important to keep records establishing the date that product is marked.

A patent holder that produces no product is not subject to the marking statute and is therefore entitled to damages prior to actual notice. Similarly, a patent consisting of only method claims is not subject to the marking statute since there is no product to mark. The patent marking statute is intended to punish the patentee contributing to the problem of innocent infringement by producing unmarked product.

While there are significant advantages to properly marking product with notice of patent coverage, one should be aware that false patent marking is something to avoid. 35 U.S. Code § 292 generally provides that anyone that marks any unpatented article with a patent marking with the intent to deceive the public may be fined up to $500 for every such offense.

Properly marking a product with a patent marking is described in the statue. It requires the magic word “patent” or the abbreviation “pat” together with an actual or virtual identification of the patent. If the character of the article does not permit affixing such notice directly on it, a label containing a like notice can be affixed to the item or to the package wherein it is contained.

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Courts have explained that compliance with the marking statute is a question of fact addressed in the damages phase of a patent infringement trial. In other words, the assessment of conformance to the patent marking statute is often made with remorseful hindsight. Additionally, there is little that can be done to cure deficiencies in conformance to the statute.


The following guidelines may be helpful to properly mark your product to maximize your recovery for damages from an infringer.

Mark your product on the actual article with the word “patent” or the abbreviation “pat” together with the patent number applied directly on the article (or as noted above, on the packaging). The Federal Circuit applies a flexible and functionalist approach when determining if the location of the mark conforms to § 287.

Alternatively, virtually mark your product or packaging with the word “patent” or the abbreviation “pat” together with an address of a posting on the internet (accessible to the public without charge) that associates the patented article with the number of the patent. Note that a list of patents on a web page without the corresponding association to products does not meet the requirements of the statute. Additionally, it is not sufficient to merely state “patented” or “patent pending” on the product or the packaging without the corresponding patent number or internet address.

Strive to mark all products consistently and continuously. In an assessment of conformance to the patent marking statute to recover damages prior to actual notice of infringement, courts will consider whether substantially all the patented products being distributed were marked, and that once marking was begun, the marking was substantially consistent and continuous. There is no hard and fast threshold over what constitutes “substantially all” since may factors may play into the assessment but strive for all products in production. Include patent marking considerations at all phases of new product introduction procedures and be sure to update patent markings when new patents are issued or acquired.

Marking a product as “patent pending” serves no useful purpose other than alerting the public that a patent has been applied for. Marking a product as “patent pending” upon the filing of a provisional patent application is perfectly acceptable, but if that provisional application is not converted to a utility application, continued marking may constitute false patent marking.

Conclusion Patent marking is a critical component of managing a patent portfolio. A patent marking strategy that is fully integrated with product development is key to properly associating products in production with the appropriate patent assets. Your patent attorney is a valuable resource for establishing the procedure, but the execution of a patent marking program is best performed in the ordinary course of business by the individuals knowledgeable of the products and informed on the patent portfolio. Additionally, the program must be continuously updated or refreshed upon the addition of an issued patent into the patent portfolio and new products into the product portfolio.

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