This paper revisits the announcement effect of foreign blockholders’ share acquisitions for 14 years from 2005 to 2018. We classified heterogeneous foreign block shareholders based on criteria such as new acquisitions, investment purposes, tax haven status and legal systems of foreign investors’ origin countries. The empirical results of the event study conducted using 1,471 disclosures, are as follows. We find positive stock returns associated with foreign investors’ block acquisitions before and after the announcement date. The positive stock returns are more pronounced in new acquisitions involving management participation. We also find the interaction effects between new acquisitions and legal systems; specifically, the ownership of foreign blockholders from tax-havens mitigates the positive impact of new acquisitions, while the ownership of foreign investors from common-law countries reinforces the impact. The results demonstrate discriminatory impact of heterogeneous foreign blockholders on firm value, depending on the characteristics of foreign blockholders. This suggests that the Korean stock market is more responsive to initial investments involving management participation by foreign blockholders from common-law countries.