Gabriel Zucman Speech at the G20 finance ministers meeting in São Paulo

I would like to talk about the future of international tax cooperation — and make the case that, building on the successes of the last decade, the logical next step of international tax cooperation should involve a minimum tax on the very rich. [...] P0-10 denotes the 10% of adults at the bottom of the pre-tax income distribution, P10-20 the next decile, etc. [...] Depending on the countries, this tax planning can involve the use of different legal structures, such as holding companies or trusts, but the outcome is the same: the income tax fails to properly tax the individuals with the highest ability to pay taxes. [...] Because the notion of income is not well-defined at the very top-end of the distribution (as wealthy individuals can retain income in companies or other intermediate structures), this minimum tax should be expressed as a fraction of wealth, which is well defined. [...] Ministers of Finance of the major economies of the globe have an important role to play in this regard.