How does invention depend on personality? Do inventors differ from noninventors? This study investigated the personal factors influencing a sample of independent inventors in Germany (N = 69). Standardized psychological questionnaires were employed to assess the Big Five personality dimensions, willingness to take risks, self-concept, and self-efficacy. For a comparison with noninventors, scores from reference samples were taken. Hypotheses were formulated based on research into creativity and entrepreneurship and the normative DABEI Stage Model of invention. As expected, the independent inventors showed higher levels of extraversion and openness to experience. In addition, independent inventors stood out in terms of emotional stability (low neuroticism scores). Surprisingly, in this sample success as an inventor correlated negatively with openness to experience. The interpretation is along the lines that inventors may work in a focused manner and technical implementation of an innovative idea may be optimized with great persistence. Discussion centers around the generalizability of the results.