Data brokers—also called information brokers—are businesses that aggregate, process, and license information to other companies. While some data they sell is environmental or statistical, they often combine data about individual people from multiple sources to create lists of email addresses, phone numbers, or physical addresses that can be sold to marketers.

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Guinness, H. (2022, May 25). How data brokers threaten your privacy. Popular Science. https://www.popsci.com/technology/data-brokers-explained/