"Why should we reward firms for successfully gaming the tax system when we in turn are called on to make up the missing tax revenues?" said Kleinbard, a former corporate tax attorney at Cleary Gottlieb Steen & Hamilton LLP. "Much of these earnings overseas are reaped from an enormous shell game: Firms move their taxable income from the U.S. and other major economies -- where their customers and key employees are in reality located -- to tax havens."