We find that the age discontinuity of politicians around 18 years old in 1978, who had already joined the Chinese Communist Party (CCP) or joined soon thereafter and later became municipal paramount leaders, has had a lasting effect on contemporary firm- and city-level policies. In particular, firms in cities with mayors that joined the CCP under the ideological regime of Mao have made more social contributions, lowered within-firm pay inequality, and engaged in less internationalization than those under Deng’s regime. These effects are stronger in firms with political connections, in non-state-owned enterprises, and in regions that are more market-oriented and not “revolutionary bases.” We find further evidence that ideology-induced corporate policy biases have some impact on firm performance and valuation.