In trademark litigation, the owner of a trademark must prove that the defendant's use of the same or a similar trademark is likely to cause confusion. See 15 U.S.C. §1114 (infringement of registered marks) and 15 U.S.C. §1125 (false designation of origin). In California, the Ninth Circuit Court of Appeals applies the following likelihood of confusion factors:  strength of the mark;  proximity of the goods;  similarity of the marks;  evidence of actual confusion;  marketing channels used;  type of goods and the degree of care likely to be exercised by the purchaser;  defendant's intent in selecting the mark; and  likelihood of expansion of the product lines. The list is not exhaustive and other variables may come into play depending on the particular facts presented.
The remedies for trademark infringement can include plaintiff's damages, defendant's profits and injunctive relief. In trademark counterfeiting cases, statutory damages between $1,000 to $200,000 (non-willful) or even up to $2,000,000 (willful) may be available.
We have litigated a variety of trademark infringement actions, including actions in federal court, involving trademarks or source identifiers related to Cobra Golf, Playboy, Porsche, Ceasars's Casino, Michael Jackson, Green Day, and the Rolling Stones.
The United States Patent and Trademark Office ("USPTO") explains that "A trademark is a brand name. A trademark or service mark includes any word, name, symbol, device, or any combination, used or intended to be used to identify and distinguish the goods/services of one seller or provider from those of others, and to indicate the source of the goods/services." www.uspto.gov/trademarks/basics/index.jsp. See also15 U.S.C. §1127. For instance, the word "Nike" and the symbol of the Nike swoosh on shoes are trademarks that indicate the source of the shoes is Nike, Inc. and helps Nike, Inc. distinguish its shoes from its competitors.
A trademark is created by use of the trademark on goods in commerce as a source identifier. Although federal or state registration of a trademark/servicemark is not required, the USPTO explains that federal registration "has several advantages, including notice to the public of the registrant's claim of ownership of the mark, legal presumption of ownership nationwide, and exclusive right to use the mark on or in connection with the goods/services listed in the registration." See www.uspto.gov/trademarks/basics/index.jsp.