Extant research underscored that user-innovators, especially those belonging to communities can be excellent collaborators with firms seeking new ideas. The two characteristics significant for commercial success are community membership and information disclosure. However, recent national surveys in Japan and the U.S. reveal that these characteristics are a part of the minority group of user-innovators. This study aims to investigate the differences in characteristics and motives between such a minority and the majority of user-innovators. We conducted a survey in Japan and classified 579 user-innovators into three groups - social, revealing, and silent innovators. Significant differences were observed in demographic variables, innovation adoption rates, and motives for product development. Based on the results, this study discusses how firms can effectively co-opt and integrate each type of user-innovator into their organizations' innovation processes.