This study examines whether, how and why an entrepreneur's gender influences firm innovativeness. Drawing upon research on gender-segregated educational and employment experiences, we suggest that firms led by women will exhibit less innovation breadth and depth than those led by men due to differences in the degree to which male versus female entrepreneurs resemble ‘jacks-(or jills)-of-all trades’. Analysis of survey data collected from 900 business owner-managers in Germany lends overall support—albeit with some noteworthy exceptions. Our findings point to the need for an even more nuanced approach to research at the nexus of gender, entrepreneurship, and innovation.