Capping a six-month investigation, the International Consortium of Investigative Journalists (ICIJ) and its media partners are publishing a secret cache of leaked tax documents and dozens of news stories that show how multinational corporations throughout the globe routed profits through tiny and wealthy Luxembourg to reduce their taxes.

Today’s release marks the first time that these documents have been made public.

The leaked files provide an inside look at a hidden world where corporations can meet with Luxembourg officials to obtain favorable tax treatment. ICIJ journalists have combed through the documents and found that some corporations can reduce their effective taxes to less than 1 percent on profits they have shuffled through Luxembourg.

“This is the first time, really, that we’ve seen inside the workings of Luxembourg as a tax haven,’’ said Richard Brooks, a former U.K. tax inspector and author of The Great Tax Robbery, who was hired by ICIJ to help review the documents. “The countries that are … losing money, they don’t know about it, don’t know how it operates at all.”

Stories based on the documents will be published on ICIJ’s Luxembourg Leaks website as well as in international partner publications, including The Guardian, Le Monde, CNBC, the Canadian Broadcasting Corporation and many others. ICIJ journalists have reviewed nearly 28,000 pages of confidential documents from more than 340 companies. Working in different time zones and countries, they have shared information and collaborated to produce today’s report.

Tax experts were drawn in to decipher many of the documents. Reporters visited Luxembourg and interviewed key officials. A team of more than 80 journalists in 26 countries worked on the project. The tax documents that will be released today include nearly 550 individual rulings from 2002 to 2010.

“What this shows once again is the power of collaborative cross-border reporting,” said Gerard Ryle, director of the ICIJ. “Journalists in different countries have reviewed the documents relevant to their own communities and then shared their findings.”

ICIJ reporting shows exactly how Luxembourg allows taxes to be drastically reduced. At the center is the country’s Ministry of Finance, eager to approve these arrangements and the business they bring to the country. Then there are thousands of tax advisers and consultants from major accounting firms devising increasingly complicated tax avoidance strategies – for a fee. And benefiting from it all are hundreds of global corporations using Luxembourg to reduce billions in taxes that would otherwise go to their own home countries.

Companies seeking tax deals from Luxembourg came from manufacturing, private equity, real estate, banking, the pharmaceutical industry and many more, the leaked records show. They include big names such as Pepsi, IKEA, FedEx, Abbott Laboratories, American International Group (AIG), Amazon, Blackstone, Procter & Gamble, H.J. Heinz and JP Morgan Chase.

The ICIJ investigation comes at a time when the European Union has become more serious on clamping down on tax avoidance as the continent’s economic crisis continues. Luxembourg’s tax policies have helped contribute to an estimated $1 trillion loss for European governments as a result of corporate tax avoidance and evasion, according to a 2012 report prepared for the European Parliament.

In the United States, corporations with foreign operations and the ability to move money across the globe have now parked some $2 trillion in profits overseas to avoid paying U.S. taxes, according to an often-cited report by Audit Analytics, a Massachusetts-based research firm.

The European Commission currently has opened investigations into three European tax havens: Ireland, the Netherlands and Luxembourg. It is looking into whether Luxembourg tax rulings involving Fiat Finance and Amazon constitute illegal state aid that prohibits countries from offering special tax relief to some companies and not all.

The commission has also opened an infringement case against Luxembourg over its failure to produce some documents that the Brussels regulators have requested. Many of the documents to be released today are of the type sought by Brussels officials. Documents obtained by ICIJ include some tax filings involving Amazon, one target of the commission’s probe.

Luxembourg’s former Prime Minister, Jean-Claude Junker, is the commission’s incoming president, one of the most powerful positions in Europe. It was during his 18-year tenure as prime minister that many of Luxembourg’s laissez-faire tax policies were enacted.

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