In his seminal contribution, Baumol (1990) proposes that the direction of entrepreneurial effort towards its productive (e.g., start-up activity) or unproductive (e.g., rent-seeking) use in a society depends on institutions or the “rules of the game”. We focus on an important micro-foundation of Baumol's theory namely that certain individuals change the direction of entrepreneurial efforts with institutional change. Our research contrasts with previous work on the role of institutions, which mostly focuses on the aggregate macro-level, while not observing individual behavior. We analyze who decides to start a venture in East Germany after the fall of the Berlin Wall and find that many individuals who demonstrated commitment to the anti-entrepreneurial communist regime in the GDR were active in launching new ventures soon after German re-unification. We argue that commitment to communism among post-communist entrepreneurs reflects rent-seeking. Once institutions change radically, entrepreneurial efforts are directed towards start-up activity. We rely on the German Socio-Economic Panel Study (SOEP) that includes information on whether East German respondents had a telephone before German re-unification, which was one of the most sought-after rewards for commitment to the regime. We find that telephone owners had a higher propensity of becoming successful firm founders. Telephone owners were also more likely to have an entrepreneurship-prone personality profile and value orientation. Our results confirm Baumol's theory and suggest that alertness to entrepreneurial arbitrage opportunities is guiding the redirection of entrepreneurial effort in the face of drastic institutional change.