Sony K.K. v. Yugen Kaisha Walkman

Sony K.K. (plaintiff) began using the term Walkman as a trademark in 1979 in connection with its popular portable cassette-tape players. By 1980, the trademark had become well-known in Japan. Sony also licensed the mark for use on a wide range of products, including shoes and clothing, and exercised control over the quality of such products. Yugen Kaisha Walkman (Yugen) (defendant) operated a small store that sold shoes and clothing that were manufactured by others. In connection with that business, Yugen placed the term Walkman in both English letters and katakana, a form of Japanese writing primarily used for words of foreign origin, on various items, including shopping bags, receipts, price tags, advertisements, and signage. Unlike Sony’s trademark, the English version of Yugen’s mark incorporated an image of a shoe. Yugen’s mark was also in a stylized font, whereas Sony used block letters. One of Sony’s marks consisted only of the English word Walkman, but others incorporated katakana as well. Sony commissioned a survey of 500 individuals living in Tokyo or Chiba City. In Tokyo, 83.3 percent of respondents associated the term Walkman with Sony; in Chiba City, 76 percent of respondents associated the term with Sony. Fewer respondents in each city recognized the Walkman as a portable tape player. Sony sued Yugen for trademark infringement.