https://www.theverge.com/2018/3/28/17174854/facebook-shutting-down-partner-categories-ad-targeting-cambridge-analytica

Facebook announced today that it’s disabling a form of advertising targeting called Partner Categories, which allowed prominent third-party data aggregators like Experian and Acxiom to provide clients with offline data like purchasing activity to inform ad targeting. The move comes amid the fallout from the ongoing Cambridge Analytica data privacy scandal, and it follows similar moves from the social network to curtail abusive ad practices. Those include a momentary pause on third-party app approval announced today and new limitations imposed on the volume and type of data third-party apps are given through APIs like Facebook Login announced last week.

As pointed out by Recode, Partner Categories is not what allowed Cambridge Analytica to access as many as 50 million Facebook profiles. The data mining firm was given that data from a third-party app developer in violation of Facebook’s terms of service and without user permission. Rather, data aggregators are able to supplement companies with data they may not otherwise have, allowing marketers and Facebook itself to work together to better target users.