Senate investigators are accusing Apple of wiring together a complicated system to shield billions of dollars in international profits from both U.S. and foreign tax collectors, reports “Politico” (http://tinyurl.com/kp3hh77).

A report released ahead of Apple CEO Tim Cook’s inaugural Capitol Hill appearance today alleges the tech giant took advantage of numerous U.S. tax loopholes and avoided U.S. taxes on US$44 billion in offshore, taxable income between 2009 and 2012. Apple denies this.

The bipartisan Senate probe also charges that the company’s long established foreign entities, based in Ireland, don’t actually have tax-resident status there or anywhere else. Apple conducts most of its international business in the European country to take advantage of lower tax rates, according to the congressional report.