Resumen
This study aims to investigate the influence of corporate governance in financial efficiency of Brazilian companies listed on the BOVESPA. Quantitative-descriptive, 284 companies were analyzed data from 2008 to 2013 to check the evolution over the years of financial efficiency and, in the year 2013 to estimate the influence of corporate governance. We evaluated the corporate governance through the creation of a governance index (IGOV), proposed by Silveira (2004), for the dimensions access to information content of public information, structure of the board of directors and ownership and control structure. The calculation of the financial efficiency of the companies was carried out by using the data envelopment analysis (DEA) and to his analysis, he used the social networking analysis technique with 6.0 UNCINET software and the statistical package STATA 11.0. As a result it was found that the financial efficiency of the banks, over the six years analyzed, remained stable and higher than the companies, both in relation to the equivalent percentage of companies with maximum efficiency, as compared to the overall rate of efficiency. It was found that the corporate governance influences the financial performance of companies negatively in the size structure of the board and positively by the ownership structure. The results for banks showed the positive influence of access to information and negative for the information content and the structure of the board. This study helps to identify the dimensions of corporate governance that influence the efficiency of companies and banks and also cooperates with the identification of effective institutions over six years.