A trademark (also written trade mark or trade-mark) is a type of intellectual property consisting of a recognizable sign, design, or expression that identifies a product or service from a particular source and distinguishes it from others. A trademark owner can be an individual, business organization, or any legal entity. A trademark may be located on a package, a label, a voucher, or on the product itself. Trademarks used to identify services are sometimes called service marks.
The symbols ™ (the trademark symbol) and ® (the registered trademark symbol) can be used to indicate trademarks; the latter is only for use by the owner of a trademark that has been registered.
A trademark identifies the brand owner of a particular product or service. Trademarks can be used by others under licensing agreements; for example, the Lego Group purchased a license from Lucasfilm to be allowed to launch Lego Star Wars. The unauthorized usage of trademarks by producing and trading counterfeit consumer goods is known as brand piracy.
The owner of a trademark may pursue legal action against trademark infringement. Most countries require formal trademark registration as a precondition for pursuing this type of action. The United States, Canada, and other countries also recognize common law trademark rights, which means action can be taken to protect any unregistered trademark if it is in use. Still, common law trademarks offer to the holder, in general, less legal protection than registered trademarks.
As the purpose of the trademark is to identify a particular source of the product, rather than the product itself, it is widespread legal advice that trademark owners should always use their trademarks as adjectives modifying a generic product name, and set off with capitalization or a distinctive typeface, as a guard against the trademark becoming the generic name of the product. Thus "LEGO bricks" rather than "some Lego" or "Legos". The name of the producer itself is a "trade name" rather than a trademark and can be used as a noun.
Different goods and services have been classified by the International (Nice) Classification of Goods and Services into 45 Trademark Classes (1 to 34 cover goods, and 35 to 45 cover services). The idea behind this system is to specify and limit the extension of the intellectual property right by determining which goods or services are covered by the mark, and to unify classification systems around the world.
Trademarks rights must be maintained through actual lawful use of the trademark. These rights will cease if a mark is not actively used for a period of time, normally five years in most jurisdictions. In the case of trademark registration, failure to actively use the mark in the lawful course of trade, or to enforce the registration in the event of infringement, may also expose the registration itself to become liable for an application for the removal from the register after a certain period of time on the grounds of "non-use".