STEM PhDs increasingly contribute to commercial science, such as patenting. We analyze faculty's role in training STEM PhD students as new inventors on patents at leading research universities, emphasizing the drivers of gender differences. We ...STEM PhDs are a critical source of human capital in the economy, contributing to commercial as well as academic science. We examine whether STEM PhD students become new inventors (file their first patent) during their doctoral training at the top 25 U.S. ...