The gas leak disaster in Bhopal, India, in 1984 illustrates a situation of catastrophe and mass torts resulting in loss of life and health as well as environmental degradation. The Indian company Union Carbide India Limited, who owned and operated the chemical plant that caused the disaster, did not have sufficient assets to compensate the victims in contrast to its financially well-equipped US parent company Union Carbide Corporation. The courts never reached a decision regarding parent company liability for the subsidiary’s debts arising from tort claims against the subsidiary. However, where the subsidiary cannot satisfy its tort creditors, as in the Bhopal case, questions regarding parent company liability become highly relevant in relation to both foreign and domestic subsidiaries. Therefore, parent company liability for subsidiaries’ torts is discussed in this thesis with reference to Swedish and UK company law and with a focus on the tort creditors’ situation and the business and human rights debate. From limited liability for shareholders and each company being a separate legal entity follows that a parent company is not liable for its subsidiaries’ debts in neither Swedish nor UK company law. These concepts serve the important function of facilitating risk-taking and entrepreneurial activities. However, they also contribute to the problem of uncompensated tort victims arising where a subsidiary is involved in liability- producing activities but lacks assets to compensate the tort victims. Where limited liability and each company being a separate legal entity leads to particularly inappropriate results, the doctrine of piercing the corporate veil in both Sweden and the UK allows the court to disregard the separate legal personalities and hold the parent company liable for its subsidiary’s acts or omissions. The doctrine is characterised by uncertainty and is seemingly only available under exceptional circumstances. The doctrine does little to mitigate the problems for subsidiaries’ tort creditors at large. The business and human rights debate calls for access to judicial remedies for victims of businesses’ human rights violations. As some human rights violations can form the basis of a tort claim, it is relevant to discuss parent company liability according to company law in relation to human rights violations. The United Nations Guiding Principles on Business and Human Rights emphasise the need to ensure that corporate law does not prevent access to judicial remedies. However, the company law regulation of liability in company groups seems in practice to function as an obstacle for access to judicial remedies for human rights victims, particularly when also considering the inadequate legal regimes in some host states and the hurdles of jurisdiction and applicable law in multinational company groups. It is concluded in this thesis that the company law regulation of liability in company groups is seemingly not equipped to meet the challenges arising with the development of company groups, the global reach of the private business sector, the risks of mass torts and the influence of the business sector on human rights.