MOLITOR has advised a major company specialised in medical devices and technology regarding the Luxembourg dispositions concerning the treatment of personal data. The data were collected by Luxembourg medical practitioners at the occasion of post-operative medical consultations and then rendered anonymous before being transferred to our client, and possibly to other entities of the latter (established notably in the United States). The issue in this case was to define whether the treatment of anonymous data can be considered as a treatment of personal data under the Luxembourg legal provisions or not and whether our client had therefore to compelled with theses rules.