Section 15 Incontestability: When and How to File
By Casey Scott McKay ·
After five consecutive years of continuous use following registration, the owner of a mark on the Principal Register can file a declaration under Section 15 of the Lanham Act, 15 U.S.C. § 1065, that converts the registration from prima facie evidence into conclusive evidence of validity, ownership, and the exclusive right to use. This guide walks through the filing stage by stage: the six eligibility gates, the difference between the automatic five-year bar in 15 U.S.C. § 1064 and the optional filing you actually make, how to pick between a standalone Section 15 and a combined Sections 8 and 15 declaration, and how to audit the use record before anyone signs a verified statement. It gives current USPTO fees, realistic timelines, model declaration language, a decision tree for the awkward cases, and an annotated example carried from docket entry to notice of acknowledgment. It also draws the boundary honestly: incontestability does not defeat genericness, functionality, abandonment, fraud, prior common-law users, descriptive fair use, or the Trademark Modernization Act's never-used cancellation ground. The last sections cover Madrid Section 71 registrations, Section 2(f) marks, chain-of-title problems, post-registration office actions, and the handful of situations in which the right move is to wait.
IP and Technology > Trademarks | Guide | Published 15 January 2026 - Updated 27 January 2026 | Casey Scott McKay - marksy.us
Summary. After five consecutive years of continuous use following registration, the owner of a mark on the Principal Register can file a declaration under Section 15 of the Lanham Act, 15 U.S.C. § 1065, that turns the registration from prima facie evidence into conclusive evidence of validity, ownership, and the exclusive right to use. This guide walks the filing stage by stage — the six eligibility gates, the difference between the automatic five-year bar in 15 U.S.C. § 1064 and the optional declaration you actually file, how to choose between a standalone Section 15 and a combined Sections 8 and 15 filing, and how to audit the use record before anyone signs a verified statement. It gives current USPTO fees, realistic timelines, model declaration language, a decision tree for the awkward cases, and an annotated example carried from docket entry to notice of acknowledgment. It also draws the boundary honestly: incontestability does not defeat genericness, functionality, abandonment, fraud, prior common-law users, descriptive fair use, or the Trademark Modernization Act's never-used cancellation ground. Closing sections cover Madrid Section 71 registrations, Section 2(f) marks, chain-of-title problems, post-registration office actions, and the handful of situations in which the right move is to wait.
Keywords: section 15 declaration · incontestability · 15 usc 1065 · conclusive evidence · section 33(b) defenses · section 8 declaration · continued use · trademark maintenance · uspto post-registration audit · combined sections 8 and 15 · park n fly · merely descriptive defense · cancellation grounds · principal register · specimen of use · trademark fraud · section 71 madrid · docketing deadlines
This is premium Marksy content — the full document is available to subscribers.