We investigate whether founder participation in research and development collaborations enhances the two components of absorptive capacity: potential absorptive capacity and realized absorptive capacity. Based on a longitudinal firm-patent dataset of over 700 collaborations, we find that founder involvement enhances potential absorptive capacity provided the knowledge bases of focal firm and partner are related. Once knowledge has been absorbed, founder involvement increases realized absorptive capacity irrespective of relatedness. Thus, we highlight the merit of treating the components of absorptive capacity separately by showing differing effects of founder-involvement. Further, our paper emphasizes the outstanding role founders play in their firms.