To assist participants in planning changes and implementations, a mock trading session of the PUMA Trading System will be held on May 24th, 2025, with market participation.

In this session, the following system and infrastructure changes will be validated:

• EntryPoint FIX and Binary - Order Entry Interface: Update of Technical Specification to Include a New Field for Risk Assessment:

 A new optional field, named "Trading Sub-account," will be implemented to provide greater flexibility in account management during trading sessions. If the "Trading Sub-account" is specified, it will be exclusively utilized by the LiNe system for assessing trading limits, disregarding the information in tag 1-Account.

• Binary Market Data -  Launch of Order Book Management Based on Price/OrderID and Template Update:

On May 26, 2025, the Order Book Management based on Price/OrderID will be launched in the Binary Market Data. The update to template file 2.1.0 will be carried out for the tranche listed below:

Both book management mechanisms (priority and position) will be supported simultaneously at the launch.

1. Mock trading session timetable
2. Morning test of the electronic trading system

It is mandatory for all the firms to participate in the morning test, which will be held on May 26^th, 2025 (Monday), from 7:00 a.m. to 7:45 a.m. for the derivatives market and from 7:00 a.m. to 8:00 a.m. for the equities market in both production environments.

3. Participation confirmation:

The activities to be performed during the test can be found in the mandatory script. Market data for these instruments will be sent during the mock trading session.

Participation in the mock trading session must be confirmed no later than 12 noon on May 23th, 2025 (Friday), exclusively by email at [email protected] with “Mock trading session” in the subject line, identifying the institution, naming the individuals who will participate and supplying their contact details (telephone numbers and email addresses).

In response to this confirmation, the participant will receive the mandatory test script and must fill it out and send it to the above email address.

Please note that mock trading session participants must adjust their internal systems so that the results of the mock trading session are completely segregated from real trading sessions.

Further information can be obtained from B3 Services – Trading, by telephone on +55 11 2565-5021/5022.