What are Panama Papers? Are offshore accounts legal?

Here are five frequently asked questions on the biggest leak in whistleblower history...

With the 'Panama Papers' scandal unfolding all over the world and across the media, here are five frequently asked questions on the story:
1 - Just what are the Panama Papers?
They are leaks of 11.5 million tax documents from law firm Mossack Fonseca on offshore financial dealings of billionaires, politicians and global leaders.
2 - Who exposed, who probed?
The information was obtained from anonymous sources by the German newspaper Süddeutsche Zeitung, which gave it to the ICIJ. The ICIJ then shared it with others.
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3 - What is the ICIJ?
The ICIJ is a body of 190 reporters, journalists, analysts spanning more than 65 countries and focused on eradicating cross-border crime, global corruption and abuse of power and position.
4 - What is Mossack Fonseca?
The law firm was established in 1977 in Panama with offices in 42 countries. Its services: setting up companies in offshore places and wealth management.
5 - Is the business crooked?
Offshore entities and transactions are legal. People use such avenues for reasons of inheritance, security, and even currency curbs.
Related:
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(Source: Wires, Agencies, Indian Express, The Guardian, ICIJ, Net)