A case which belongs to one of the statutory categories (see: In what cases can group proceedings be commenced?) can be examined in group proceedings if certain additional formal conditions, defined as preconditions for admissibility of group proceedings, are met. They have been briefly defined below and they include:
- homogeneity of claims of all group members – this means that all group members should seek the same claim from the defendant (raise claims for the granting of the same manner of legal protection, g.by seeking to be awarded specified amounts of money from the defendant). Hence, a situation where some of the group members only request the establishment of the defendant’s liability whereas others seek to be awarded damages from the defendant, is not allowed;
- common factual basis of the claims – demands of all group members pursued in group proceedings should be based on the same (eidentical) or, at least, similar (equal) factual basis, therefore they must result either from one and the same event (e.g. from one transport accident or railway catastrophe) or from several events bearing similarity to one another (e.g. the same type of agreement in the form of a repeated contractual template, including the same abusive clauses, concluded by several consumers or the use of the same product that proved to be hazardous which caused harm to several individuals). Therefore, they should have their source not so much in the same legal relationship, but in the same type of a legal relationship. In other words, all the demands should either be based on the same entire factual basis or share only such common circumstances which prejudge the occurrence of each of the claims. Whereas the legal basis of individual claims, i.e. whether it is identical or not, is of no significance;
- the size (number of members of the group) – group proceedings are possible when at least ten persons establish a group to pursue claims. The group can include both natural and legal persons, or the so-called entities without corporate status (unlimited partnerships, general partnerships, limited partnerships);
- standardized pecuniary claims – this is an additional precondition for pursuing claims in group proceedings, which applies only in a case of pursuit of pecuniary claims in group proceedings (g. monetary claims for damages). The standardised amount of the claims means that the group members – as an entire group or within the subgroups of at least two persons – must pursue the payment of a standardised sum from the defendant (see: What can you pursue in group proceedings?).