We examine to what extent market conditions facilitating start-up formation affect firms' R&D investment and
profits. We consider a model in which R&D efforts of an incumbent firm generate partly tacit technological
know-howembodied in a key R&D employee,who might use it to forma start-up. The availability of complementary
assets influences whether new firms are created and determine expected profits for start-up's founders. A
large availability of complementary assets has the direct effect that the generation of start-ups is fostered.
However, as a strategic effect, the incentives of incumbents to invest in R&D may be reduced because of the
increased danger of knowledge loss occurring through start-up formation. We characterize the effects of an
increase in the availability of complementary assets, showing that counter-intuitively there are cases in which
it induces an increase in incumbents' R&D investment.