González Cabañas, JoséCuevas Rumín, ÁngelArrate Galán, AritzCuevas Rumín, Rubén2021-04-272021-04-272021-01Communications of the ACM, 64(1), Jan. 2021, Pp. 62-690001-07821557-7317 (online)https://hdl.handle.net/10016/32490Citizens Worldwide have demonstrated serious concerns regarding the management of personal information by online services. For instance, the 2015 Eurobarometer about data protection13 reveals that: 63% of citizens within the Eurpean Union (EU) do not trust online businesses, more than half do not like providing personal information in return for free services, and 53% do not like that Internet companies use their personal information in tailored advertising.8engCopyright held by authors/owners. Publication rights licensed to ACM.Advertising data processingSensitive dataData analysisFacebookDoes Facebook use sensitive data for advertising purposes?Does Facebook use sensitive data for advertising purposes? worldwide analysis and GDPR Impactresearch articleTelecomunicacioneshttps://doi.org/10.1145/3426361open access62169COMMUNICATIONS OF THE ACM64AR/0000026941