Tzero Group Inc. (TZERL: Grey Market) | Symbol Change Fri, Jun 19, 2020 12:00 - Tzero Group Inc. ( TZERL : Grey Market) - Symbol Change - The symbol, TZERL, is no longer a valid symbol for Tzero Group Inc.. As of Fri, Jun 19, 2020, the new trading symbol is TZROP. You may find a complete list of symbol changes at otcmarkets.com .