Research question The secondary research use of treatment data has the potential to expand medical knowledge and improve patient care. Hospitals play an important role in systematic secondary research use: they generate large amounts of treatment data and are supposed to establish the necessary structures for their use in research. This raises the ethical question: do hospitals have a moral duty to support secondary research use of treatment data by establishing and operating the necessary resources and infrastructure? Procedure Our aim (...) is to outline a conceptual framework to discuss the question and to propose a first normative position. Building on insights from business and organizational ethics, we develop a conceptual framework in which we view hospitals as moral actors. Our normative-ethical analysis is based on a reconstructive stakeholder approach, in which we identify the following general duties of hospitals: orientation towards patient wellbeing; cost efficiency; enabling employees to act in accordance with professional ethical standards; supporting public health and research. We examine whether these general duties provide reasons for a specific duty of hospitals to support secondary research use of treatment data. We discuss potential objections to such a duty arising from other, potentially conflicting general duties of hospitals (e.g., data protection), from practice (e.g., costs/resources), or related discourses (data ownership). Conclusion Certain general duties (orientation towards patient wellbeing, cost efficiency, support of public health) justify a duty of hospitals to support secondary research use of treatment data. The duty to enable employees to act in accordance with professional ethical standards is only an indirect reason; the duty to support research applies solely to university hospitals. Potential objections apply to a certain extent but can be mitigated through targeted measures. (shrink)