Toward the end of 2023, two US-based broker-dealers were subjected to multi-million dollar penalties levied by the Financial Industry Regulatory Authority (FINRA) on grounds of failure to provide “best execution” to their customers. The timing of these sanctions coincided with the introduction by the Securities and Exchange Commission (SEC) of Regulation Best Execution (Reg NMS Rule 606) – the first regulation specifically targeting best execution, as the SEC increases its scrutiny of the actions of broker-dealers in light of their customer obligations.