On the basis of a sample of 149 graduate firms from five German business incubators, this article contributes to incubator/incubation literature by investigating the effects of the age of the incubators and the firms’ incubation time in securing long-term survival of the firms after leaving the incubator facilities. The empirical findings from Cox proportional hazards regression and parametric accelerated failure time models reveal a statistically significant negative impact for both variables incubator age and incubation time on post-graduation firm survival. One important implication that follows from the empirical results for policy makers and managers of those initiatives is that, when incubator managers become increasingly involved in various regional development activities, this may reduce the effectiveness of incubator support. Also, our finding speaks in favour of a strict limitation of incubation times and reinforces arguments of the supporters of maximum tenancy.