A question often raised is whether one has to register their trademark in order to be protected. Stated another way, if someone has been using a word or symbol to identify their goods or services and never bothered to file a federal trademark registration application, can they sue if someone else engages in what would amount to a trademark infringement.
The answer to that question is “Yes”. A federal claim under the Lanham Act for an infringement of an unregistered mark is triggered by a use which is “likely to cause confusion, or to cause mistake, or to deceive as to the affiliation, connection, or association” of the user with the senior user. [Lanham Act §43(a), 15 U.S.C.§1125(a)]. The law does not distinguish between what is called “common law” rights in a trademark and rights derived from federal registration.
“Likelihood of confusion” is the basic test of both common-law trademark infringement and federal statutory trademark infringement. [Friend v H.A. Friend & Co. 416 F.2nd 526 (9th Cir. 1969].
Lanham Act Section 43(a) protects qualifying unregistered trademarks against infringement [Two Pesos, Inc. v. Taco Cabana, Inc. (1992) 505 U.S. 763, 112 S. Ct. 2753, 120 L. Ed. 2d 615, 623 ; see Transgo, Inc. v. Ajac Transmission Parts Corp. (9th Cir. 1985) 768 F.2d 1001, 1013 ]. The principles for determining whether an unregistered mark qualifies for protection and has been infringed are generally the same as those that apply to actions for infringement of a registered mark.
While an unregistered user of a trademark has some protection against infringement and acts of unfair competition, one gets greater rights by obtaining a federal registration of a trademark. The differences are substantial and there are no reasons not to obtain federal registration.