FinCEN is the US Financial Crimes Enforcement Network. These are the people at the US Treasury who combat financial crime. Concerns about transactions made in US dollars need to be sent to FinCEN, even if they take place outside the US.
These documents - Suspicious Activities Reports or SARs - are some of the international banking system's most closely guarded secrets. Banks use them to report suspicious behavior but they are not proof of wrongdoing or crime.
The FinCEN files are more than 2,500 documents, most of which were sent to the US authorities between 2000 and 2017. They raise concerns about what their clients might be doing.
They were leaked to Buzzfeed News and shared with a group that brings together investigative journalists from around the world, which distributed them to 108 news organizations in 88 countries.
