This paper aimed to study poison pills, investigate the conceptual aspects, as well as legal dispositions and other rules applicable. A research of publicly-held firms that use this anti-takeover instrument was done, sampled till June 2006, in order to discover peculiarities in the Brazilian environment. Moreover, as an objective of this paper, some theories that can explain the behavior of managers from poison pill firms were presented, focused on the classical agency problem: managers' interest against firms' interest. This exploratory study should support the development of a new empirical research area in Brazil. Theories here presented can and should be investigated in future research, in order to improve Brazilian literature focused on this matter. Nevertheless, it would be prudent to consider the idiosyncratic aspects of the Brazilian Stock Market and precocity of these poison pill firms in empirical studies, before coming to any conclusion about the figures and measures obtained.
Poison pills; Publicly-held firms; Hostile take over; Tender offer
