Originally from Collective Litigation in Europe: Law and Practice – Preview Page

Collective actions are regarded as a considerable new phenomenon in Hungarian law. Previously, litigation of multiple plaintiffs in a single procedure was available through joinder of claims which remained a viable alternative under the newest procedural law, especially in cases where a smaller contingent of claimants is involved. 
Codification of collective actions have always been induced by foreign impacts in Hungary. The first example of procedures that can be considered collective was a product of harmonization of laws in the ‘90s when Hungary made steps to become a member state of the European Community. The implementation of Directive 93/13/EC, having entered into effect on March 1, 1998, enabled certain public authorities and associations representing consumer interests and business entities to bring a declaratory action for establishing the invalidity of terms and conditions. Later, the declaratory action against unfair terms and conditions relating to consumer contracts was introduced in the Old Code Civil.1 After several years, public-interest actions granting monetary relief beside declaratory action were implemented in sectoral laws in the field of consumer protection.2 
In 2013, the codification work of the (new) Code of Civil Procedure began. The Government wished to established general rules on collective actions following international trends promoting collective redress mechanisms.