Abstract: When an Automated Clearing House (ACH) fund transaction is deemed to have suspicious nature, the ACH transfer file for the transaction may be marked with a unique key (dye pACH). The unique key may be used to track the transfer paths of funds through a plurality of financial institutions. Thus, the suspicious ACH fund may be tracked through the plurality of financial institutions. Law enforcement entities, such as police or Federal Bureau of Investigation (FBI) may use the unique key to track suspicious fund transfers through a plurality of financial institutions to detect money laundering or fraud activities or obtain high-level understanding of cybercrime organizations.