Consent provenance and compliance tracking over a complex consumer data supply chain using blockchain distributed ledger

A method for consumer opting out, comprising the method steps of:

• a. at an original data server, receiving a consumer message requesting an opt out for use of consumer data pertaining to such consumer;
• b. calling a first consent application programming interface (API) at a first peer node of a plurality of peer nodes to enter the opt out and a consumer identifier (consumer ID) in a consent ledger at the first peer node, wherein the first peer node is one of the plurality of peer nodes forming a distributed peer node network;
• c. syncing the opt out in the consent ledger at the first peer node with each of the other peer nodes;
• d. detecting, at a second consent ledger at a second peer node using a second subscription API, that the consumer has opted out, and sending through the second subscription API to a transferee server an opt-out message;
• and
• e. detecting, at a third consent ledger at a third peer node and using a third subscription API, that the consumer has opted out, and sending through the third subscription API to an advertising server an opt-out message, wherein any or all of the first, second, and third peer nodes may be the same peer node.