The Marking Requirement: Here is how the marking statute has been interpreted.
- If a patentee sells (or authorizes the sale of) a product that is covered by the patent, the patentee can only collect past-damages for patent infringement if either (1) the product was properly marked as patented or (2) the infringer had actual notice of its infringement and continued to infringe.
- If there is no authorized product covered by the patent, then the patentee can collect past damages (up to six years) even if the infringer had no knowledge of the patent. Method claims typically do not have a corresponding product. However, there is some debate about the collection of past-damages without notice for method claims when the patent also includes apparatus claims that cover an authorized product.
Thus, the seeming plain language of 35 USC 287 does not apply. Section 287 indicates that “[i]n 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.” Courts have held that this section does not apply if the patentee had nothing to mark.
This background law was described by the Supreme Court in its 1936 case captioned Wine Ry. Appliance Co. v. Enter. Ry. Equip. Co., 297 U.S. 387 (1936). In that case the court held that “issuance of a patent and recordation in the Patent Office constitute notice to the world of its existence.” Interpreting a precurser to today’s marking statute, the Supreme Court wrote that “[p]enalty for failure [to mark] implies opportunity to perform.”