This dataset is the online appendix to the research paper "How German Manufacturing Firms Manage Sustainability Regulation Microfoundations of a Dynamic Capability" (21st International Conference on Wirtschaftsinformatik, WI 2026). It documents the qualitative, two-stage research design. First, the expert interview study: the structure of the interviews, an overview of the 14 anonymized interviewees by sector, the number and types of questions, and the development of the interview guideline. Second, the verb-based content analysis of corporate sustainability reports: the action-verb list with sources and the analyzed reports. The materials support the transparency and reproducibility of the reported findings.