E.I. DuPont de Nemours & Company (plaintiff) owned the trademark for “TEFLON” for non-stick pots and pans. Yoshida International, Inc. (defendant) manufactured the “EFLON” zipper. DuPont sued Yoshida for trademark infringement. Yoshida argued that TEFLON had become a generic term and thus was not eligible for trademark protection. Yoshida introduced two consumer surveys that asked for the name of the non-stick feature. Of the respondents that were aware of the feature, 86.1 percent of respondents in one survey and 81.4 percent in the other responded solely with TEFLON as the name. Only 7.3 percent and 9.1 percent, respectively, of those that were aware named DuPont as the manufacturer. DuPont introduced a consumer survey that identified a series of names and asking for each name whether it was a brand name or a common name. 68 percent of respondents identified TEFLON as a brand name; 31 percent identified TEFLON as a common name.