By combining new macroeconomic statistics on the activities of multinational companies with the national accounts of tax havens and the world’s other countries, we estimate that close to 40% of multinational profits are shifted to low-tax countries each year. Profit shifting is highest among U.S. multinationals; the tax revenue losses are largest for the European Union and developing countries. We show theoretically and empirically that in the current international tax system, tax authorities of high-tax countries do not have incentives to combat profit shifting to tax havens. They instead focus their enforcement effort on relocating profits booked in other high-tax places—in effect stealing revenue from each other. This policy failure can explain the persistence of profit shifting to low-tax countries despite the sizable costs involved for high-tax countries. We provide a new cross country database of GDP, corporate profits, trade balances, and factor shares corrected for profit shifting, showing that the global rise of the corporate capital share is significantly under-estimated.