title: Comment on "Unique in the shopping mall: On the reidentifiability of credit card metadata".
abstract: De Montjoye et al. (Reports, 30 January 2015, p. 536) claimed that most individuals can be reidentified from a deidentified transaction database and that anonymization mechanisms are not effective against reidentification. We demonstrate that anonymization can be performed by techniques well established in the literature.
authors.affiliation: United Nations Educational, Scientific, and Cultural Organization (UNESCO) Chair in Data Privacy, Department of Computer Engineering and Mathematics, Universitat Rovira i Virgili (URV), Avenue Països Catalans, 26, E-43007, Tarragona, Catalonia. david.sanchez@urv.cat.
authors.forename: David
authors.initials: D
authors.lastname: Sánchez
authors.affiliation: United Nations Educational, Scientific, and Cultural Organization (UNESCO) Chair in Data Privacy, Department of Computer Engineering and Mathematics, Universitat Rovira i Virgili (URV), Avenue Països Catalans, 26, E-43007, Tarragona, Catalonia.
authors.forename: Sergio
authors.initials: S
authors.lastname: Martínez
authors.affiliation: United Nations Educational, Scientific, and Cultural Organization (UNESCO) Chair in Data Privacy, Department of Computer Engineering and Mathematics, Universitat Rovira i Virgili (URV), Avenue Països Catalans, 26, E-43007, Tarragona, Catalonia.
authors.forename: Josep
authors.initials: J
authors.lastname: Domingo-Ferrer
mesh_terms: D003132:Commerce; D003625:Data Collection; D005260:Female; D006801:Humans; D033181:Information Dissemination; D008297:Male; D018907:Privacy