Skip to main content

Patent Marking Requirements: Patented Articles Must be Marked as Patented in Order For Patentee to Recover Damages Due to Patent Infringement

Patented articles (products, devices, items, etc.) must be marked as patented if patentee is to be awarded damages resulting from infringement of the patent. The marking provisions of the patent statute are within 35 U.S.C. § 287(a). 35 U.S.C. § 287(a) states:

Patentees, 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, may give notice to the public that the same is patented, either by fixing thereon the word "patent" or the abbreviation "pat.", together with the number of the patent, or when, from the character of the article, this cannot be done, by fixing to it, or to the package wherein one or more of them is contained, a label containing a like notice. In the event of failure so to mark, no damages shall be recovered by the patentee in any action for infringement, except on proof that the infringer was notified of the infringement and continued to infringe thereafter, in which event damages may be recovered only for infringement occurring after such notice. Filing of an action for infringement shall constitute such notice.

Marking provides constructive notice to the world of the patent, and is an important issue in many patent infringement suits. For patentees, they must consider the patent marking provisions of the patent statute prior to release of a patented article to the public. For defendants, they may be able to avoid paying for damages if patentee did not properly mark the article. It is important to point out that the patent marking provisions apply only to situations where there is a tangible thing that can be marked as patented.

In Nike, Inc. v. Wal-Mart Stores, Inc., 138 F.3d 1437 (Fed. Cir. 1998), the Court of Appeals for the Federal Circuit (the "Federal Circuit") summarized the purposes of the marking statute as:

  1. to avoid innocent infringement, Wine Ry. Appliance Co. v. Enterprise Ry. Equip. Co., 297 U.S. 387, 395 (1936);
  2. to encourage patentee to give notice to the public that the article is patented, American Medical Sys. v. Medical Eng'g Corp., 6 F.3d 1523, 1537 (Fed. Cir. 1993) Cert. denied, 511 U.S. 1070.; and
  3. allowing the public to determine whether an article is patented, Bonito Boats Inc. v. Thunder Craft Boats Inc., 489 U.S. 141, 162 (1989). As cited in Nike, Inc., 138 F.3d at 1443.

Among many issues, several important points to consider in analyzing the marking provisions are:

  1. Was the article marked?
  2. Does the patent include claims to a process and an article?
  3. If there was marking, was it sufficient? And,
  4. In the absence of marking was there notice to the defendant?

(1) Was the article marked?

"In the event of failure so to mark, no damages shall be recovered by the patentee in any action for infringement[.]" 35 U.S.C. § 287(a). This phrase may be interpreted in at least two ways. First, that damage recovery is entirely barred even if the marking deficiency is later cured. Or, second, damage recovery is barred for the period of the marking deficiency only. The Federal Circuit interpreted the no damages provision of § 287(a) to mean that patentee is precluded from recovery of damages for the entire time prior to full compliance with the marking provisions of the § 287(a). Ameircan Medical Sys., 6 F.3d 1523, 1537. Therefore, once the patentee cures the marking deficiency, it may recover damages for infringement from the time of curing forward.

Therefore, patentee must mark a patented article. If patentee fails to mark the patented article as it is released to public view through marketing, sales, promotion, or other such endeavors, then patentee will not be able to capture pre-marking damages even if they are successful in proving infringement. However, patentee can cure the marking defect by simply starting to mark. After the date of compliance with the marking statute, patentee can capture damage awards. On the other side, defendant may be able to take advantage of the marking provisions to avoid payment of damages.

(2) Does the patent include claims to a process and an article?

Marking is not required if the patent is directed to a process or method. Bandag, Inc. v. Gerrard Tire Co., Inc., 704 F.2d 1578, 1581 (Fed. Cir. 1983), citing Wine Ry. Appliance Co, 297 U.S. 387. The reason is straight forward: when a patent is directed to a process or method there is nothing to mark. American Med. Sys., Inc., 6 F.3d at 1538.

Problems with this straight forward rule about marking develop when a patent claims both a process and an article. The article may be claimed directly or through product by process claims. In either case there is a thing that can be marked and a process within the patent. In 1983 the Federal Circuit ruled that if only process claims are found to be infringed, then patentee may recover pre-marking damages, even if the claimed product was not proven to be sufficiently marked. Hanson v. Alpine Valley Ski Area, Inc., 718 F.2d 1075, 1083 (Fed. Cir. 1983). In 1993 the Federal Circuit seemed to refine this rule by stating that the distinction for allowing pre-marking damage recovery for patentee that fails to prove sufficiency of marking is whether patentee alleges infringement of only the process claims or both the process and device claims. Pre-marking damage recovery might be allowed in the case where patentee only alleges infringement of process claims. Devices for Medicine, Inc. v. Boehl, 822 F.2d 1062, 1066 (Fed. Cir. 1993). The Federal Circuit seemed to deal harshly with these rules later by stating clearly that if there is a tangible item to be marked, then it must be marked in order to recover damages. American Med. Sys., Inc., 6 F.3d at 1538. However, in American Med. Sys., patentee asserted infringement of both process and device claims. Further, apparent harshness towards the Hanson and Devices for Medicine cases was directed more towards the litigants framing of the rules rather than the rules themselves.

Safe advice for the patentee is that if patentee has a process that produces a tangible product that can be marked, then it should do so prior to release to the public. If patentee has failed to do so and is now engaged in infringement litigation, it may be more likely that damages would be recovered if patentee only asserts infringement of process claims. A defendant faced with a suit alleging infringement of product and process claims, where the product was unmarked, may be successful in evading paying damages by arguing non-compliance with the marking provisions by the patentee.

(3) If there was marking, was it sufficient?

The patentee must mark enough of the product to insure success in enforcing the patent. Marking must be substantially consistent and continuous in order to provide constructive notice to the public. American Med. Sys., 6 F.3d at 1538. "Substantially consistent and continuous" makes a very nice phrase, but does not offer specific guidance to how much marking will suffice. The trend seems to be that substantially all product must be marked all of the time. Nike, Inc., 138 F.3d at 1446-1447.

The patentee must mark the product or the packaging for the product. Marking literature associated with the product but not part of the product or the packaging is probably not sufficient to satisfy the marking provisions of § 287(a). Calmar, Inc. v. Emson Research, Inc., 850 F. Supp. 861, 868 (C.D. Cal 1994). When both the product and the packaging could be marked courts vary on whether marking of only the packaging is sufficient. Courts vary from a strict rule that if it is possible to mark the product, then it must be marked, to a more lax standard that allows excuse of marking packaging rather than product if there is a sufficient reason why it was impractical or undesirable to mark the product. See, for an example of strict adherance, Stryker Corp. v. Intermedics Orthopedics, Inc., 891 F. Supp. 751, 860 (E.D.N.Y. 1995), aff'd, 96 F.3d 1409 (Fed. Cir. 1996). See, for examples of excuses, Rutherford v. Trim-Tex, Inc., 803 F. Supp. 158 (N.D. Ill. 1992).

Patentee should be advised to mark every single product that is released to the public. Additionally, if the product cannot be marked because of its characteristics then patentee should mark the actual packaging that contains the product. The patentee should not rely on listings of patents in associated literature. Defendant should look for patentees failure to mark all of the product or the actual packaging containing the product.

(4) In the absence of marking was there notice to the defendant?

The patentee may remedy a failure to mark by giving actual notice to the alleged infringer of the patent. However, in that case damage recovery will only be possible for damages occurring from the date of actual notice and forward. To conform to the actual notice provision, patentee must make an affirmative communication of a specific charge of infringement. Amsted Indus. Inc. v. Buckeye Stell Castings Co., 24 F.3d 178, 187 (1994). Actual notice may include filing of an infringement suit. 35 U.S.C. § 287(a). Additionally, actual notice is achieved when the recipient of the notice is advised of the patent at issue, the activity that patentee believes is infringement, and a proposal to abate the problem, including licensing offers. SRI Int'l v. ATL, Inc., 127 F.3d 1462, 1470. It is irrelevant whether the alleged infringer had knowledge of the patent or even their own infringement from independent sources. The burden is on patentee to cure the marking defect by providing actual notice. Amsted Indus. Inc., 24 F.3d at 187.

Under these standards patentee should be advised that if they have failed to mark, but now wish to stop the allegedly infringing activity, they should notify the alleged infringer by letter. The letter should include a recitation of the patent number(s) at issue, identification of the products that patentee believes are infringing, and a request that alleged infringer stop infringing or an offer to license. If those items are included in a notification letter to alleged infringer, then patentee may recover damages from the point of actual notice forward.


A patentee must mark a patented article with the appropriate language such as "Pat. 1,234,567" or "Patent 9,876,543." If the article cannot be marked then the packaging that contains the article must be marked. Substantially all of the articles released to the public in any manner must be marked all of the time. In the absence of proper marking patentee may not be able to recover a damage award for the period of time where marking was improper. If patentee discovers marking problems and an alleged infringer, they can cure the marking problem by delivering actual notice to the alleged infringer. The actual notice must identify the patent by number, the allegedly infringing activity, and a proposal to abate the infringement. The proposal to abate may be a request that the alleged infringer cease, or an offer to license. By providing actual notice the patentee will be able to recover damages for infringement that occurs from the time of actual notice forward. When a patent includes process and article claims, then patentee must mark the tangible item. If patentee does not mark the tangible item, then patentee might be able to recover damages for infringement occurring prior to notice by asserting only the process claims. Defendant should assert violations of these requirements in order to avoid paying damages for alleged infringement.

Was this helpful?

Thank you. Your response has been sent.

Copied to clipboard