A computer-implemented method for managing access to data stored within a data source is provided. The method includes receiving updated account data including an updated account identifier, and at least one subscription rule for verifying that a merchant is authorized to receive updated account data. The method also includes storing the updated account data and the at least one subscription rule. The method further includes receiving a registration request from a requesting merchant including at least one candidate account identifier and one merchant identifier identifying the requesting merchant, and retrieving the at least one subscription rule after matching the candidate account identifier to the updated account identifier. The method further includes applying the at least one subscription rule to the requesting merchant, determining that the requesting merchant is authorized to receive the updated account data, and transmitting an update response to the requesting merchant including the updated account data.