Patent Marking

Patent marking gives constructive notice of a patent to the world — enabling the patent owner to recover damages from the beginning of infringement rather than from the date of actual notice: STATUTORY BASIS: 35 U.S.C. § 287(a): if a patent owner makes, offers for sale, or sells a patented article without marking it with the patent number, they cannot recover damages for infringement that occurs BEFORE the infringer had actual notice of the patent; DAMAGES LIMITATION: without marking, damages begin only from the date the infringer received actual notice of the infringement — either a specific notice letter or filing of the infringement lawsuit; with proper marking, damages begin from the date the infringer first began infringing (potentially years earlier); EXAMPLE: Company A has a patent, makes the patented product, but doesn't mark it; Company B starts infringing in Year 1; Company A files suit in Year 4; without marking, Company A can only recover damages for Year 4 forward (after lawsuit = actual notice), or from whenever it sent a demand letter; with marking, Company A could recover for all of Years 1-4; CONSTRUCTIVE NOTICE: proper marking puts the public on constructive notice that the product is patented; a potential infringer cannot claim ignorance of the patent when the product is clearly marked; MARKING IS NOT REQUIRED: it is voluntary; if you mark properly, you can recover pre-notice damages; if you don't mark, you can still sue for infringement but damages start only from actual notice; DESIGN PATENTS: § 287 applies equally to design patents — must mark 'Patent D' plus the patent number; METHOD CLAIMS ONLY: if a patent has ONLY method claims (no apparatus/product claims), § 287's marking requirement does NOT apply — method claims cannot be marked on a product.

Patent marking has specific form requirements under § 287 and the AIA's virtual marking provision: TRADITIONAL MARKING (PHYSICAL): the word 'Patent' or 'Pat.' followed by the patent number(s); affixed to the patented article; where impossible to affix, affixed to the package; FORMAT: 'Patent 10,000,000' or 'Pat. 10,000,000'; multiple patents can be listed on the product or package; AIA VIRTUAL MARKING (2011): Congress added § 287(a)'s virtual marking alternative: instead of printing every patent number on every product, mark 'Patent' or 'Pat.' followed by a URL pointing to a publicly accessible webpage that lists the patent numbers; example: 'Pat. patentmarking.example.com'; the webpage must be freely accessible to the public (no login required); the webpage must list the patent number(s) and the products they cover; ADVANTAGE OF VIRTUAL MARKING: eliminates need to re-label products every time a new patent issues or an old one expires; a single URL can cover a portfolio of patents that changes over time; CONSISTENCY REQUIREMENT: marking must be consistent — if a patent owner marks some patented articles but not others, § 287's limitation still applies to the unmarked articles; LICENSEE MARKING OBLIGATION: if a patent owner licenses the patent, the licensee's products must also be marked; if the licensee fails to mark, the patent owner cannot recover pre-notice damages for the licensee's period of non-compliance — unless the patent owner takes reasonable steps to ensure compliance; CANNOT MARK IF PRODUCT ISN'T PATENTED: false marking of unpatented articles as patented violates § 292 (false patent marking); after the AIA, qui tam suits for false marking were eliminated — only the United States or an entity that suffered competitive harm can sue.

Failure to mark can significantly truncate a patent owner's damages period: LIMITATION ON DAMAGES PERIOD: § 287(a) states: '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 after the notification'; ACTUAL NOTICE REQUIREMENT WHEN NOT MARKING: the infringer must receive actual notice — not constructive notice from published patents or industry knowledge; actual notice has two forms: (a) SPECIFIC NOTICE LETTER: a letter identifying the specific patent(s) and the specific accused products or conduct; Amsted Industries v. Buckeye Steel (Fed. Cir. 1994): notice must be specific, not just a general royalty demand; (b) FILING SUIT: the filing of an infringement complaint constitutes actual notice; DAMAGES BEGIN AFTER ACTUAL NOTICE: once actual notice is received, the defendant's continued infringement is subject to damages; CALCULATING LOST PERIOD: if infringement began in 2020, and the patent owner had an un-marked patented product, and didn't file suit until 2024, the patent owner loses damages for 2020-2024 (the pre-notice period); this can be millions of dollars in lost recovery; PLAINTIFF'S BURDEN: the patent owner bears the burden of proving compliance with § 287; if the defendant raises failure to mark as a defense, the plaintiff must prove it was marking properly or that the patent has only method claims; CURE: beginning to mark cures the failure to mark going forward; but cannot retroactively recover the pre-marking period; PATENT ACQUISITION: if you acquire a portfolio of patents, check whether the patented products are being marked; failure to mark before acquisition affects the seller's damages period, not the buyer's — but buyers should mark immediately upon acquisition.

Patent marking has important implications when multiple parties are involved in making, using, or selling patented products: LICENSEE'S DUTY TO MARK: if a patent owner licenses the right to make, use, or sell the patented article, the licensee must also mark its products; failure by the licensee to mark triggers § 287's limitation for the patentee's recovery as well; THE PATENT OWNER CANNOT RECOVER PRE-NOTICE DAMAGES: if neither the patent owner nor the licensee marks the articles, the patent owner cannot recover damages for infringement that occurred before actual notice; this is true even if the patent owner itself always marked — if the licensee failed to mark and the licensee's products were sold alongside the infringing products; REASONABLE STEPS DEFENSE: if the patent owner took reasonable steps to monitor and ensure that licensees were marking, and the licensee failed anyway, the patent owner may argue it was not responsible for the licensee's failure; what constitutes 'reasonable steps' is fact-specific; AFFIRMATIVE LICENSE MARKING OBLIGATION: include explicit marking obligations in patent license agreements; add: (a) the obligation to mark with the patent number; (b) the obligation to use virtual marking consistent with the licensor's program; (c) audit rights to verify marking compliance; MULTI-PATENT PRODUCTS: a product covered by multiple patents must list all patent numbers (or a virtual marking URL covering all of them); failing to list one patent number for an article covered by multiple patents limits recovery on the unlisted patent; FOREIGN PRODUCTS: § 287 applies only to the United States — foreign sales of patented articles that are never sold in the US do not require marking for US damages purposes; but if the same foreign-made product is later sold in the US, it should be marked.

False patent marking — marking a product as patented when it isn't — exposes the marker to civil liability: STATUTORY BASIS: 35 U.S.C. § 292: 'Whoever marks upon, or affixes to, or uses in advertising in connection with any unpatented article, the word patent or any word or number importing that the same is patented, for the purpose of deceiving the public... shall be fined not more than $500 for every such offense'; FOREST GROUP RULING (Fed. Cir. 2009): each article falsely marked is a separate 'offense' — not each marking decision; for a company that makes 1 million falsely marked products, that's up to $500 million in potential exposure; AIA REFORM (2011): Congress limited standing to sue for false marking; PRE-AIA: any person could bring a qui tam action on behalf of the US government and share the penalties; this created a cottage industry of false marking suits filed by attorneys targeting companies that failed to update product markings after patent expiration; POST-AIA: only TWO entities can sue for false marking: (a) the United States (rare); (b) a person who has suffered a COMPETITIVE INJURY from the false marking; mere member of the public with no competitive harm cannot sue; EXPIRED PATENT SAFE HARBOR: marking with an expired patent number is NOT false marking if: the product was covered by the patent during its term; the marking was not made with intent to deceive; this safe harbor protects companies that mark products with a patent that has since expired from retroactive liability; INTENT TO DECEIVE: § 292 requires 'for the purpose of deceiving the public' — a scienter requirement; innocent mistakes are not false marking; BEST PRACTICES: implement a marking compliance program; review markings when patents expire; remove expired patent numbers or use virtual marking (which is easier to update).