Public-interest civil action against an arbitration center (1ª Câmara de Conciliação e Arbitragem de Rio Verde). Claim for a preliminary injunction ordering the arbitration center to cease its activities in disputes involving consumer relations. Reversal of the injunction in view of the possibility, pursuant to a precedent of the Superior Court of Justice (STJ), for the consumer to take the initiative of instituting the arbitration proceedings or to expressly agree to its institution at a moment subsequent to the execution of the contract: