Although network activities have been shown to positively affect a corporation's performance, the mechanisms through which a specific corporate network position exerts its influence on firm performance are not well understood. We study 162 corporations of various industries to hypothesize that the relationship between a particular corporation's network posture and its later performance is mediated by its innovativeness. For doing so, we go far beyond recent studies on corporate networks by highlighting different effects of a corporation's network centrality, its location towards structural holes, and of being part in small sub-groups. Hence, this paper applies social network analysis to the study of embedded entrepreneurial corporations and offers a theoretical framework how the external-oriented network perspective and internal-oriented innovativeness interact to influence future performance. Our results consistently support our hypothesized mediation model. Moreover, by using data over a period of six years, we address the important issue of causality.