Obama pledged during his campaign to shut down the ability of U.S. corporations to avoid paying taxes by shipping their income to offshore havens. As a senator in 2007, he joined Levin in proposing similar legislation to curb abuse of offshore tax operations and force companies to be more transparent about their overseas operations in those jurisdictions.

Some critics of the loophole argue that the secrecy in tax-haven countries may hide shady accounting at some businesses. Members of Congress say that investigators at the Internal Revenue Service are outgunned in trying to track down who is crossing the line and who is not. "This is a basic issue of fairness and integrity," Obama said in introducing the 2007 bill. "We need to crack down on individuals and businesses that abuse our tax laws so that those who work hard and play by the rules aren't disadvantaged."