Spain's stock market regulator has imposed a fine of €5 million ($5.8 million) on Elon Musk's platform X for failing to ensure that Quantum AI, a cryptoasset firm, had authorization for its investment services. The penalty, dated November 3, reflects Spain’s efforts to control cryptoasset advertising risks since 2022. Mexico City’s CNMV stated, “X did not fulfill its duties” in vetting the firm’s legitimacy. X may appeal the decision in Spain's High Court.