Common-law trademark
Common-law (unregistered) trademark
Definition
A common-law trademark is an unregistered mark that becomes enforceable through actual use in commerce, without any registration filing. Protection is geographically limited to where the mark is actively used and recognized. Owners can use ™ but not ®. They can pursue passing-off and unfair-competition claims but typically have weaker remedies than registered-mark holders.
Verbatim from the source
“An unregistered trademark, sometimes informally called a common law trademark, is an enforceable mark created by a business or individual to signify or distinguish a product or service.”
Technical detail
Practical implication for naming: USPTO TESS only shows you registered (or applied-for) federal marks. A name that is clear of federal registrations may still collide with a common-law mark used by an active business in a regional market — and that business may be able to prevent your use within their territory of established reputation.
Catching common-law marks requires checking where real products live, not where lawyers file. NameVerdict's Lane 3 (common-law collisions) checks GitHub repositories, iTunes apps, Reddit mentions, Product Hunt launches, Crunchbase entries, and Etsy listings — places where unregistered businesses actually establish use-in-commerce evidence.
Common-law protection exists in jurisdictions including the U.S., U.K., Canada, Australia, India; varies in other countries that rely more heavily on registration-based regimes.
Where it appears
- NameVerdict Used here
Lane 3 (Common-law collisions) is the lane built specifically to catch this category. Searches GitHub, iTunes, Reddit, Product Hunt, Crunchbase, and Etsy in parallel.
Related terms
- USPTO TESS
USPTO TESS — recently rebranded as Trademark Search — is the U.S. Patent and Trademark Office's free public database of every federal tradem…
- Nice class
Nice Classification is the international system that organizes goods and services into 45 classes (1–34 for goods, 35–45 for services) for t…