This research assesses two individual differences—general self–efficacy and regretful thinking—in the context of technological innovation. Results, obtained from a random sample of 217 patent inventors show that both general self–efficacy and regretful thinking distinguish inventors who started a business (i.e., technological entrepreneurs) from inventors who did not start a new business (i.e., technological nonentrepreneurs). More to the point, patent inventors, who at the time of our survey were actively involved in new business formation, tended to have significantly higher self–efficacy. Also, while technological entrepreneurs tended to have stronger regrets about business opportunities, technological nonentrepreneurs tended to have stronger regrets regarding career and education decisions. The two groups did not differ in terms of the quantity of these regrets. Implications for theory, practice, and future study of individual differences in entrepreneurship are discussed.