Systems and methods for effectively anonymizing consumer transaction data

Systems and methods are described that anonymized consumer transaction data in such manner to prevent de-anonymization to reveal personally identifiable information (PII) of the consumers. The process includes selecting particular consumer transaction data, generating a dictionary of items, generating consumer groups, matching consumer transaction data for each consumer to a group, forming modifiable consumer transaction histories, and quantifying a similarity between consumer groups. In some embodiments, the process includes discarding consumer groups that contain less than a threshold number of consumers, selecting at least one consumer group that contains at least a threshold number of consumers as the anonymized consumer transaction dataset, and providing the anonymized consumer transaction dataset to a third party for analysis.