This paper studies the contextual factors that influence whether invention occurs during work time or leisure time. Leisure time invention, a potentially important but thus far largely unexplored source of employee creativity, refers to invention where the main underlying idea occurs while the employee is away from the workplace. We build on existing theory in the fields of organizational creativity and knowledge recombination, especially work relating context to creativity. The paper’s main theoretical contribution is to extend our understanding of the boundaries of employee creativity by adding to the discussion of how access to and exploitation of different types of resources—during work hours or during leisure time — may affect creativity. Based on survey data from more than 3,000 inventions from German employee inventors, we find that leisure time inventions are more frequently observed for conceptually based problems, in cases where interactions with people outside the organization are important for making the invention, and for smaller research and development projects. Our findings also suggest that employee inventions during work time may become more “embedded” in an environment of path-dependent resources than those made during leisure time.