The abuse of a dominant position based on the collection and processing of personal data is a competition law issue under German law. The value of data is the value of advertising on social networks. Inadequate data processing by Facebook has harmed both users and po-tential competitors. The Bundeskartellamt has focused its recent decision on efficiency, de-spite its perspective on the application of Article 19(1) of the Act against Restraints of Com-petition, in accordance with German case-law. The impact on European competition law will depend on the controversial harmonisation of personality rights; so far, only data protec-tion law has been regulated. © 2019, Lexxion Verlagsgesellschaft mbH. All rights reserved.