A computer-based method and system for detecting violation of intellectual property rights of a digital file, comprising, in a distribution channel, digitally sending or streaming the file from a sending party to a receiving party, adding a watermark to the digital file at the sending party prior to sending or streaming the file, wherein the watermark comprises an identifier of the sending and receiving party(s), as well as a unique file ID. In one embodiment, the party is informed about user and/or customer behavior, and can take precautions.