Yes, all existing active Login IDs with permissions to the Production and/or Sandbox TFNRegistry can be used to access the Application Program Interface (API). Please Note: Users cannot use the TFNRegistry API and User Interface (UI) at the same time, with same Login ID. Currently, the TFNRegistry supports only one Active session per Login ID. If the user tries to open multiple sessions with the same Login ID, the user will be prompted with a session override message to overwrite the previous session.