The large share of international trade in the global economy implies that parts of many of the society's sectors fall under control of foreign actors. This also applies to strategically important sectors with consequences for national security, such as healthcare. Thus, many states have introduced systems to assess foreign direct investments in sectors vital to societal functions and critical infrastructure. In this study, we combine a set of case studies with a jurisprudential examination of relevant Swedish legislation and a method for risk and threat assessment, with the aim to identify vulnerabilities linked to foreign investments in the healthcare system. Data has been collected through interviews with representatives of regional healthcare authorities and private healthcare providers, respectively. The study found that the largest risk is linked to the lack of reliable information on foreign ownership and the limited awareness of security-related issues in the healthcare sector. Foreign ownership do not necessarily increase the security risk, it is rather connected to private ownership which limits the authorities oversight and control. Otherwise, the study has not identified any systematic threats and risks in the health care sector.