At the time, it was described as the biggest ever blow to the offshore world.
A statement from Mossack Fonseca said it would continue to work with authorities to “demonstrate that no crime has been committed”.
“The reputational deterioration, the media campaign, the financial siege and the irregular actions of some Panamanian authorities have caused irreparable damage, whose obligatory consequence is the total cessation of operations to the public,” it said.
The firm added that it has already cut staff across its offices, leaving it with fewer than 50 employees.
According to a report by the International Consortium of Investigative Journalists (ICIJ), in 2013 the firm employed about 600 people in more than 40 offices around the world.
As of Thursday, the firm’s website is still active but most of the information on the front page appears to have been deleted.
The leak of the papers has generated hundreds of millions in extra tax dollars for governments across the world. HM Revenue & Customs said it expected the leaks to generate £100m ($140m, €113m) in additional tax for the UK alone.
While in South Africa, the leaks have contributed to the government collecting more than ZAR3.3bn (£200m, $278m, €224m) in extra tax revenue.
The Panama Papers leak was followed in October 2017 by the Paradise Papers.
More than 13.4 million documents were stolen from Bermuda-based law firm Appleby to the German newspaper Süddeutsche Zeitung, which shared them with the ICIJ.
Appleby has taken legal action against UK newspaper The Guardian and the BBC over their reporting of the documents, which the law firm says were stolen in a hack and should not have been published.