A player is not allowed to have an open table if they have not satisfied all the valid challenges issued to them. When a player is going to open a table, they must announce it in lobby in advance and you can NOT pre-invite players to the table. If you have invited several players to a table to play them, this is NOT a true open table and these rules will not be applied to such type table, but instead, will be treated as avoiding challenges if you do NOT answer valid challenges in the lobby.