Information Services

Beginning in the late twentieth century, technological developments such as the development of the internet, increasing computer processing power and declining costs of data storage made it much easier for companies to collect, analyze, store and transfer large amounts of data about individual people. This gave rise to the information broker or data broker industry.

Brokers collect information about individuals from public records and private sources including census and change of address records, motor vehicle and driving records, user-contributed material to social networking sites such as Facebook, Twitter and LinkedIn,media and court reports, voter registration lists, consumer purchase histories, most-wanted lists and terrorist watch lists, bank card transaction records, health care authorities, and web browsing histories. The data are aggregated to create individual profiles, often made up of thousands of individual pieces of information such as a person's age, race, gender, height, weight, marital status, religious affiliation, political affiliation, occupation, household income, net worth, home ownership status, investment habits, product preferences and health-related interests. Brokers then sell the profiles to other organizations that use them mainly to target advertising and marketing towards specific groups, to verify a person's identity including for purposes of fraud detection, and to sell to individuals and organizations so they can research people for various reasons. Data brokers also often sell the profiles to government agencies, such as the FBI, thus allowing law enforcement agencies to circumvent laws that protect privacy.

...
Wikipedia