US Trademark Law/Introduction
Although trademarks are the oldest form of intellectual property and have been protected at common law for decades, they were the last to be protected by a federal statute in the US, and infringement cases were very rare until the late 19th century.
The first trademark statute, enacted in 1870, was struck down by the Supreme Court in The Trade-Mark Cases, 100 U.S. 82 (1879), for exceeding the powers granted by the patent and copyright clause of the Constitution. Congress responded with the Trademark Act of 1881, which was based on its Commerce Clause powers.
The current federal trademark statute is the Lanham Act of 1946, codified in Title 15 of the United States Code.
® or ™ or ℠?
The Lanham Act establishes a procedure for federal registration of trademarks. If a trademark meets certain qualifications, it can be listed on the Principal Register, which affords it many benefits. Other trademarks can be listed on the Supplemental Register, which exists to allow trademarks not otherwise registrable in the United States to be registered from foreign countries that require home-country registration first, and to allow registration for descriptive marks not distinctive enough to qualify for the Principal Register. Registration is not mandatory to receive trademark protection, but federal trademarks on the Principal Register receive significantly stronger protection than unregistered trademarks. Federal registration is not mandatory to receive trademark protection, but a mark owner seeking to enforce trademarks in US federal court needs either a federal registration or a violation of the Lanham Act's specific sections on false advertising or unfair competition.
Federal registration is limited to trademarks and service marks being used by the mark owner in interstate commerce. Among other criteria, federal registered trademarks may not be "immoral, deceptive or scandalous," or "disparage or falsely suggest a connection with persons, institutions, beliefs or national symbols." They may not be "merely descriptive," "deceptively misdescriptive," "primarily geographically misdescriptive," "primarily merely a surname," or "functional" without proof of secondary meaning. See 15 U.S.C. § 1052.
In addition to federal registration, each of the fifty US states has its own system of trademark registration. If a trademark meets the state's qualifications, it can be listed on the state's registry of trademarks. State registration is not mandatory to receive trademark protection or to use a state's court system to enforce trademark rights. The US federal and state trademark registration systems co-exist side-by-side. It is possible for a state-registered trademark, or a common law unregistered trademark, to have rights superior to a trademark with a valid federal registration, due to an earlier date of adoption combined with actual and continuous use.
Only trademarks on the Principal Register and the Supplemental Register can be marked with the ® symbol to denote their higher level of protection. Any trademark, including unregistered trademarks or trademarks on the Principal or Supplemental Register, can be marked with the ™ or ℠ (service mark) symbol. These symbols exist to place third parties on notice that they may infringe the trademark by using it without authorization.