This thesis investigates whether outside blockholders make any difference to target shareholder gains in takeover contests. Using a sample of 176 takeover contests between 1997 and 2004, the results indicate that the presence of at least one outside blockholder increases the initial bid premium by 16.11% and the final bid premium by 16.84%. Further tests reveal that the relationship between outside blockholder ownership is in fact a quadratic, with a turning point lying somewhere between 27% and 30%. This indicates that at low levels of ownership, the presence of outside blockholders is beneficial to the target firms' shareholders. However, as their stakes increase, the communal benefits of having a blockholder(s) are overtaken by the private benefits that the blockholder is able to extract for themselves at the expense of the target's minority shareholders. Additionally, the results indicate that this relationship is primarily driven by outside blockholders that are publicly held corporations, and that the level of ownership or degree of activism of institutional blockholders has no impact on the premium.