Under the Polish legal system, the State Treasury, as a legal counterpart of the state acting in the sphere of legal relationships pertaining to property, participates in broadly defined business transactions as, inter alia, a shareholder in limited liability companies. The author of this article makes an attempt at a comprehensive presentation of legal regulations relating to the issues of liability of the State Treasury acting in its capacity as a shareholder of such a company, while indicating the State Treasury’s liability for civil law obligations of a company in organisation; for third party damage caused by the company in the course of its operation; for the breach of obligations relating to the State Treasury’s status as the company’s shareholder; for the non performance or improper performance of contractual obligations undertaken by the company; and for the breach of EU laws, with the latter, however, arising not directly from EU laws, but from the jurisprudence of the European Court of Justice.