The Securities and Exchange Board of India (SEBI) has rejected the National Stock Exchange's (NSE) proposal to extend market hours in the derivatives segment. NSE sought an extension from 6 pm to 9 pm to align with global news flows, but SEBI cited a lack of consensus among brokers. Some brokers were hesitant due to concerns about additional costs and technological requirements. SEBI's decision underscores the importance of broker unanimity in major market changes.