In 2013, the European Commission introduced a so-called country-by-country reporting (CbCR) for EU financial institutions, demanding the annual public disclosure of certain tax-related information on a per-country basis. This data shall help tax authorities in detecting abusive tax sheltering and exert public pressure on companies to pay their fair share of tax in each country. The aim of the project is to investigate the impact of the introduction of this CbCR requirement on the institutions affected. We examine in how far the implementation of CbCR rules has influenced the profit shifting behavior of EU financial institutions. This helps to shed more light on the implications of increased transparency and on the efficiency of CbCR. The project also examines in how far the capital market reacted to the enactment of the new disclosure obligations by analyzing whether the introduction of public CbCR for European banks was reflected in the stock returns of the companies affected around different dates of the EU legislation procedure. These questions are of high relevance, especially against the background of the numerous initiatives currently proposing different forms of CbCR.