May 31, 2017

Making the Most of Your Patent: Patent Marking

4 min

You've spent years developing your invention and several more years negotiating with the U.S. Patent and Trademark Office to get a patent with claims of myriad scope. Now that your patent has issued, what happens next? The logical next step: put infringers on notice of your patent rights. This can be achieved, constructively, by marking your patented product with a patent notice.

Codified in 35 U.S.C. § 287(a), the patent marking statute sets forth how to mark a patented article with a patent notice and the incentive for such marking. The statute serves three related purposes: 1) helping to avoid innocent infringement; 2) encouraging patentees to give notice to the public that the article is patented; and 3) aiding the public to identify whether an article is patented. See Rembrandt Wireless Technologies, LP v. Samsung Electronics Co. Ltd., 853 F.3d 1370, 1383 (Fed. Cir. 2017).

Patent Marking as Constructive Notice

As a matter of law, patent marking serves as constructive notice to infringers of the patent owner's patent rights. The Federal Circuit has explained that the patent marking statute confers rights to both patent owners and the public. See id. at 1383-1384. For patent owners, patent marking puts infringers on constructive notice, and allows patent owners to potentially collect damages from the time of constructive notice. For the public, lack of marking signals the right to exploit an unmarked product's features without liability for damages until the patent owner provides either constructive notice through patent marking or actual notice.

In order to satisfy the constructive notice provision of the patent marking statute, a patent owner should (1) mark substantially all of the patented products with the patent notice, and (2) once marking has begun, the marking should be substantially consistent and continuous.1 See American Medical Systems, Inc. v. Medical Engineering Corp., 6 F.3d 1523, 1537-1538 (Fed. Cir. 1993). Though seemingly simple, the particularities of patent marking should be carefully considered in order to satisfy the statute. For example, in Rembrandt Wireless Technologies, LP v. Samsung Electronics Co. Ltd., the Federal Circuit recently remanded a novel legal issue to the district court to decide whether the patent marking statute should be considered on a claim-by-claim basis (i.e. different claims cover different commercial embodiments, but not all commercial embodiments need be marked) or patent-by-patent basis (i.e. different claims cover different commercial embodiments, and all commercial embodiments need be marked). Failing to mark, or improperly marking, will not invoke the constructive notice provisions of the patent marking statute, and the financial implications may be significant.

With the law in apparent uncertainty, all products covered by any claim of the patent should be considered for patent marking. Of course, products not covered by a patent should not be marked; false marking may result in liabilities under 35 U.S.C. § 292.

Forms of Patent Marking

Generally, the patent marking statute requires that the patent notice must be "fixed" on the patented article. If the character of the patented article does not lend itself to marking, the patent notice can be made on a label affixed to either the article or its packaging. The patent marking statute provides the following four forms of the patent notice to be affixed to the article or label:

  1. Patent [patent number],
  2. Pat. [patent number],
  3. Patent [internet address], or
  4. Pat. [internet address].

If an internet address of a website is used, the website must (1) be accessible to the public without charge for accessing the address, and (2) associate the patented article with the number of the patent. This is known as "virtual marking." Virtual marking gives patent owners flexibility to easily add or remove patents associated with a product. For example, when a new patent issues, the new patent number can be easily added to the website without modification to the product or its packaging.


Policing the market for patent infringers can be time consuming and expensive. The constructive notice provision of the patent marking statute is a powerful tool for patent owners (those practicing their inventions, in particular) to increase the potential damages for infringement, without the need to immediately identify infringers. These damages can be leveraged to extract added value in settlement and licensing negotiations. This requires, of course, a careful understanding of your patent portfolio and product offerings, as well as the requirements of the patent marking statute.

[1] These requirements extend to "[p]atentees, and persons making, offering for sale, or selling within the United States any patented article for or under them, or importing any patented article into the United States." 35 U.S.C. § 287(a).