In short: The leaker, law enforcement official, became alarmed after two "suspicious-activity reports" (SARs) filed by Cohen's bank, First Republic, went missing from a the Treasury Department's Financial Crimes Enforcement Network (FINCEN) that he leaked the rest.
First Republic is Zuckerberg's bank…Isn't he who even put them on the map through the private wealth management arm? Oh, and nice…Trump's buddy Thomas J. Barrack Jr. serves on the board.