Collective dismissal costs are an important part of employment protection legislation (EPL) and make firms' exit more costly. We show in a model with step-by-step innovations that dismissal costs spur innovation if product markets are not too competitive: technologically more advanced firms endogenously exit with smaller probability so that there is a dynamic incentive to innovate. But dismissal costs decrease the absolute value of firms and induce exit. These opposite effects and their dependence on the policy mix of EPL and product market regulation explain why empirical studies have difficulties to find a negative effect of EPL on innovation.