Faculty as Catalysts for New Inventors: Differential Outcomes for Male and Female PhD Students

STEM PhDs are a critical source of human capital in the innovation economy. However, their training may not have kept pace with expectations of their contributions, upon graduation, to commercial as well as academic science. We examine whether STEM PhDs engage in patenting as students, becoming new inventors (file their first patent) during doctoral training at leading U.S. universities. Overall, we find that 4% of STEM PhDs become new inventors while training. However, for advisees of faculty who are themselves top (prolific) inventors, this rises to 23%. Indeed, top inventor faculty train over 45% of new inventor PhDs by co-patenting with their advisees. Given concerns over gender inclusion, we also explore whether new inventors are equally distributed by gender. We find that in our sample, the share of female new inventors in patents is 9 percentage points lower than the share of female STEM PhDs. Various mechanisms explain this gap. First, female PhDs are less likely to be trained by top inventor faculty advisors than male PhDs (and more likely to be trained by the smaller number of female top inventors). Second, female PhDs (with either top inventor or other faculty advisors) have a lower probability of becoming a new inventor relative to male counterparts. Importantly, we find that male and female top inventors have similar rates of transforming their female advisees into new inventors at about 8 percentage points lower than for male advisees.