Heirs' joint claim for social insurance compensation constitutes material co-litigation under Art. 72 § 1 k.p.c.

The Supreme Court reversed the lower court's decision regarding the appellant's court fees, ruling that the heirs' joint claim constituted material co-litigation. The plaintiffs, statutory heirs of an employee, argued that the employer's failure to report the employee to the social insurance fund caused the employee's inability to receive benefits. The court determined that because the subject matter was a shared right to the deceased's estate, the heirs were material co-litigants rather than formal ones. Consequently, the employer was required to pay only a single base fee instead of separate fees for each heir.