Third-party data refers to data that is collected by one company or organization (the “third party”) from other sources, such as public records, data brokers, or other websites. This data is then sold or shared with other companies for various purposes, such as advertising or market research.

Unlike first-party data (which is collected directly by a company from its own customers) and second-party data (which is collected by one company from another company’s customers), third-party data is often less accurate and less reliable, as it is collected from a variety of sources and may not be directly relevant to a particular company’s target audience.

In recent years, the use of third-party data has come under scrutiny due to concerns about privacy and accuracy. As a result, many companies are shifting their focus towards first-party and second-party data, and are using alternative methods such as contextual targeting to reach their target audience.