The goal of this study was to measure the attitudes towards data sharing and data-collecting organizations before and after the introduction of the EU General Data Protection regulations (GDPR) among people in Germany. The data come from a three-wave split-panel web survey among people 18 years and older in Germany who were recruited from a German nonprobability online panel. In April 2018 (before the GDPR came into effect), 2,095 participants completed the Wave 1 questionnaire on device ownership, social media use, trust in different data collecting organizations, willingness to share data, general trust, awareness of and knowledge about the GDPR, and privacy concerns. In July and in October 2018 (after the GDPR came into effect), respondents from the earlier waves were invited to participate in a second and a third web survey that repeated most of the questions from the first wave. In addition to participants from the earlier waves, fresh respondents were also invited to Waves 2 and 3. A total of 2,046 (Wave 2) and 2,117 (Wave 3) respondents completed the questionnaire in the subsequent waves. 1,269 participated in all three waves.