Big U.S. firms hold $2.1 trillion overseas to avoid taxes: study

``The 500 largest American companies hold more than $2.1 trillion in accumulated profits offshore to avoid U.S. taxes and would collectively owe an estimated $620 billion in U.S. taxes if they repatriated the funds, according to a study released on Tuesday. The study, by two left-leaning non-profit groups, found that nearly three-quarters of the firms on the Fortune 500 list of biggest American companies by gross revenue operate tax haven subsidiaries in countries like Bermuda, Ireland, Luxembourg and the Netherlands.''