The objective of this work is to measure the financial effect reflected in the behavior of
certain companies’ shares listed in the Brazilian capital market and audited by Big Four
audit firms after public sanctions issued by PCAOB in the period from 2002 to 2017. To
achieve this goal, the research methodology applied was the event study, with a
quantitative approach, based on historical closing prices of shares extracted by the
Economática software. The practical implications of this study are related to the evidence
provided of how the Brazilian capital market performs the reading of facts that involve
the integrity and reputation of an independent audit firm. This research differs from the
others already published within the scope of the PCAOB, since it relates the reaction of
the Brazilian financial market in the pricing of shares after events that put in doubt the
quality of the independent service carried out by a Big Four audit firm. The results
presented by this study corroborate the semi-efficient hypothesis of the Brazilian market,
since it was possible to observe that the company mentioned in the sanction issued by
PCAOB and the companies listed in the IBOVESPA index and that are audited by
BigFour audit firms, suffered abnormal returns following the publication of PCAOB
censures in at least one of the periods analyzed for the events under study.
