The purpose of this article is to determine to what extent contract law can be used by the legislator as an instrument to support environmental protection. As a part of civil law, contract law – as a rule – only regulates the rights and obligations of the parties to a legal relationship. However, there is a tendency to use civil law (including contract law) instrumentally for the realisation of public values. The author points to existing contract law norms that may have an impact on the state of the environment. Consumer contract law provides the most examples in this respect. Especially in recent years, consumer protection acts issued by the European Union have taken greater account of the need to support sustainable consumption and environmental protection. This includes the regulation of seller's liability for non-conformity of goods, the placing of information obligations on traders relating to the environmental aspects of the goods and services offered, and the promotion of sustainable transport by enhancing passenger rights and thus promoting collective transport. To a lesser extent, the idea of promoting environmental protection is taken into account in non-consumer contract law. In business dealings, however, there is a noticeable practice of including so-called green clauses in the content of contracts to make the performance of the contract as environmentally friendly as possible.

A simple joint-stock company is a new type of capital  company under Polish law, which is to be an alternative  mainly to a limited liability company. The regulations  concerning this company provide, among others, for  a prohibition of the acquisition of its own shares and  certain exceptions from this prohibition. The aim of the  article is to analyse the new regulation concerning the  acquisition of own shares. The general assessment of the  regulations concerning the acquisition of own shares by  a simple joint-stock company is in principle positive,  despite a few minor defects. However, the author argues  that it is inappropriate to maintain as a rule the  prohibition on the acquisition of own shares. It would be  reasonable to omit this prohibition and simply indicate the  prerequisites for permissible acquisitions of own shares.