Even banks with no exposure or involvement to Danske Bank's Estonian branch - the nexus of an unprecedented global money-laundering scheme that went uninterrupted for years - could face collateral damage from the broadening scandal as international regulators look past Danske's blatant disregard for European anti-money laundering controls and toward the international financial institutions that helped enable them by clearing their transactions: such as US and European megabanks.

International banks like JP Morgan and Deutsche Bank already got burned during the catastrophic banking scandal in Latvia that almost brought down the country's financial system (the correspondent banks embarked on a wave of "de-risking" after staring down threats from regulators). Now, that scenario is playing out again, but on a much larger scale.

According to Bloomberg, the DOJ has contacted Deutsche Bank AG and Bank of America Corp. to request information about transactions they cleared for the Danish lender's Estonia branch - the epicenter of what's believed to be the largest money laundering scandal in European history.