The largest leak of secret documents in history was just released — here are its key findings

A giant leak of documents from the internal database of a global law firm based in Panama, called Mossack Fonseca, has revealed the offshore holdings of 140 politicians, public officials, and athletes around the world.

The leaks — a collaborative effort by the International Consortium of Investigative Journalists — were obtained by the German newspaper Süddeutsche Zeitung and contain over 11 million records dating back 40 years.

They amount to about 3 terabytes of data, including corporate records, financial filings, and emails. It is roughly 1,500 times as big as the 1.7 gigabytes of data dumped in 2010 by Wikileaks.

"I think the leak will prove to be probably the biggest blow the offshore world has ever taken because of the extent of the documents," Gerard Ryle, director of the ICIJ, told BBC.

While anonymous company structures hidden in offshore holdings are not illegal, the leaks reveal the extent to which many high-level political figures have relied on shell companies to conceal their wealth, launder money, or evade taxes.

A memorandum from a Mossack Fonseca partner contained in the leak reads, "Ninety-five per cent of our work coincidentally consists in selling vehicles to avoid taxes," according to The Guardian.

To that end, offshore companies can be also be used for more nefarious purposes, such as to do business with blacklisted firms or individuals.

Among those implicated are Argentine President Mauricio Macri — who was listed as a director of a Bahamas company that dissolved in 2009 known as Fleg Trading Ltd, which did business in Brazil — and the king of Saudi Arabia, who evidently used shell companies in the British Virgin islands to take out $34 million worth of mortgages for properties in London, Fusion found in a review of the documents.

Syrian President Bashar Assad and Russian President Vladimir Putin, while not directly tied to the leaks, are linked to people named in the documents.

Here are some of the key findings from the documents being reported by ICIJ, Fusion, and The Guardian, who were among the 100 different media organizations that spent a year reviewing the documents before they were released, according to the ICIJ's website:

• Provide "details on more than 214,000 offshore entities connected to people in more than 200 countries and territories."
• "Reveal the offshore holdings 140 politicians and public officials around the world" — including the prime ministers of Iceland and Pakistan, the president of Ukraine, and the king of Saudi Arabia.
• Documents in the leak are linked to the families and associates of Egypt's former President Hosni Mubarak, Libya's former leader Muammar Gaddafi, Syrian President Bashar Assad, and the president of Ukraine, Petro Poroshenko.
• While Russian President Vladimir Putin was not named in the documents, several of his closest associates were. The pattern, outlined by The Guardian, is that Putin's friends earn millions from deals that were unlikely to be secured without his help.
• The data shows that Sergei Roldugin, Putin's best friend and a professional musician, is at the center of a ring of about $2 billion in transactions cycled between Bank Rossiya and a series of offshore companies. As a result, Roldugin is in control of assets about or possibly more than $100 million, including 3.2 % of Bank Rossiya, which has been described as Putin's "crony bank."
• Include the names of "at least 33 people and companies blacklisted by the US government" for their alleged links to Mexican drug lords and terror organizations.
• Show how "more than 500 banks major banks, including HSBC, UBS and Société Générale," have driven the creation of hard-to-trace companies — roughly 15,000 of them — in offshore havens. The Saudi crown prince opened an account for his offshore company with UBS, the documents show.
• The data reveals how Icelandic Prime Minister Sigmundur Gunnlaugsson had an undeclared interest in Iceland's bailed-out banks. Gunnlaugsson bought the offshore company Wintris in 2007. He failed to declare his interest in the company when entering parliament in 2009.

Business Insider hasn't reviewed all the documents and is unable to verify their authenticity.

Mossack Fonseca has defended its practices, telling The Guardian in a statement that "it is legal and common for companies to establish commercial entities in different jurisdictions for a variety of legitimate reasons, including conducting cross-border mergers and acquisitions, bankruptcies, estate planning, personal safety, restructuring and pooling of investment capital from different jurisdictions in neutral legal and tax regimes that does not benefit or disadvantage any one investor."