A map of key "tax haven clients" around the world, including the daughter of Ferdinand Marcos and top Spanish art collector Carmen Thyssen-Bornemisza. (ICIJ/CBC News)

A long-term analysis of more than 2.5 million leaked e-mails and financial documents, conducted by several news organizations, has shed some rare light on the secretive network of tax havens and offshore accounts where a number of the world’s elite park their fortunes.

The International Consortium of Investigative Journalists culled through 260 gigabytes of data -- more than 2.5 million files, most of them e-mails -- to produce the new report. The leaked data, originally stored on a single computer hard drive, “arrived in the mail” after the ICIJ published an expose on Australia’s Firepower scandal, but the group doesn’t specify where (or whom) it came from.

The data is still pretty dense, despite ICIJ’s mind-boggling analysis. That’s a product of the immensity of the offshore system. This data set alone included information on 122,000 offshore trusts in 10 tax havens, including the British Virgin Islands, home to 40 percent of the world’s offshore accounts and shell companies. And while the analysis may not nail down how these quasi-legal financial channels are structured and run, it does hint at how prevalent offshore accounts have become, especially among the upper crust.

The elites exposed in the report include the daughter of Philippine dictator Ferdinand Marcos, the deputy speaker of Mongolia’s parliament, the husband of a Canadian senator, Azerbaijan’s first family and one of the world’s top art collectors. The Mongolian speaker, Bayartsogt Sangajav, said he’s considering resigning over the exposure of his $1 million Swiss bank account.

Some other interesting revelations:

  1. The largest shares of the people setting up offshore accounts live in China, Hong Kong, Taiwan, Russia or another former Soviet republic.
  2. In turbulent Greece, both the upper and middle class are increasingly keeping their money in undeclared accounts -- a situation that finance officials have since vowed to investigate.
  3. A number of the world’s largest collectors use offshore accounts to buy and sell art without paying taxes.
  4. Offshore accounts are popular in Russia, where President Vladimir Putin has repeatedly asked politicians to stop using them: the deputy prime minister's wife and top managers of Russian military contractors and government-controlled companies are thought to have secret offshore investments.
  5. Offshore accounts are a major source of investment in China and Russia. China’s second-largest source of capital investment is the British Virgin Islands.

You can read the full ICIJ report here.