The Supreme Court of Cassation, with its ruling no. 26509, published on 20 November 2020, reaffirmed a principle by which company collective agreements apply erga omnes to all company workers, even if they are not members of negotiating trade unions. Exceptions are workers who joined a different trade union organisation and disagreed with the agreement. Protecting the collective interests of the company’s working community and inseparability of the regulations justifies the company collective agreements’ “erga omnes” effectiveness. This time, a group of workers went before a judicial authority to obtain overtime payment from their employer, (they were drivers for a transport company), calculated according to the increases set by the national collective labour agreement, minus the amount in the pay slip for the same reason. The judges of the first and second instance rejected the appellants’ claim stating the overtime remuneration was correctly calculated and paid using the company’s supplementary collective agreements applicable to all employees. The Court of Cassation confirmed the application of supplementary agreements and pointed out the claimants were not linked to a dissenting trade union organisation, as they referred to those agreements in their claims