The European Securities and Markets Authority (ESMA) has released a list of data contributors to the equity Consolidated Tape Provider (CTP). This list includes trading venues that are mandated to contribute data and those that can opt-in. Trading venues choosing to opt-in must begin transmitting data within 30 days of notifying ESMA. ESMA will continuously update this list as trading venues start or cease operations, or change their opt-in status. Entities wishing to opt-in must inform ESMA directly and also notify their National Competent Authority. The next update to this published list is scheduled for January 2026. MiFIR mandates ESMA to maintain this list, identifying who is required to contribute data, who can voluntarily join, and who has already opted in. Not all trading venues are required to contribute; smaller venues, particularly those not part of a large group or with a high concentration of newly listed instruments, are exempt unless they choose to participate.