Is inter-firm labor mobility a channel of knowledge spillovers? Evidence from a linked employer-employee panel

An employer-employee panel is used to study whether the movement of workers across firms is a channel of unintended diffusion of R&D-generated knowledge. Somewhat surprisingly, hiring workers from others' R&D labs to one's own does not seem to be a significant spillover channel. Hiring workers previously in R&D to one's non-R&D activities, however, boosts both productivity and profitability. This is interpreted as evidence that these workers transmit knowledge that can be readily copied and implemented without much additional R&D effort.