The purpose of the article is analyse how essential the issue of personal data protection is in the procedure of leading a collective dispute. In order to make some findings in this matter, the dogmatic and legal method was primarily used and the provisions of the Act on Resolving Collective Disputes and the GDPR were analysed in the first place. The findings made lead to the conclusion that despite the fact that the dispute itself is collective, both parties (both the trade union and the employer) process a range of personal data during the dispute. Due to the specifics of the procedure and the fact that the Act was essentially created before the GDPR came into force and it was not amended for the inclusion of broadly understood requirements for the correctness of the processing of personal data, it is necessary to rely on general principles resulting from the GDPR, and a certain indicator of it may be opinions issued by the PDPO.
The issue raised in this paper has so far been included in certain statements from the doctrine, but its practical significance and importance for social partners who execute their constitutional right to lead collective disputes fully justify further research in this direction as well as the fact of findings resulting from that research reaching various target groups (apart from the above-mentioned social partners, representatives of the judicature and science should also be reached).