IJF SOR 18.1.3.32. The correct preparation of the judogi and belt is the responsibility of the athlete and fixing is allowed once per judoka per contest. Further occasions are penalized with shido. Please note that the belt cannot be untied without the permission of the referee.
Athletes must enter and leave the field of play wearing their judogi in the proper way. If the judogi and/or belt becomes undone during the contest the athlete is obliged to quickly fix it back to the correct position. This can be between Mate! and Hajime! or during any break in action. The referee will award a penalty (shido or hansoku-make if it is the third penalties) towards the athlete(s) who does not re-adjust their judogi correctly between the mate and the subsequent Hajime!.
To intentionally disarrange his own or his opponent’s judogi; to untie or retie the belt or the trousers without the referee’s permission; to intentionally lose time arranging his judogi and belt.
The referee should never touch an athlete’s judogi or belt; this can happen in exceptional cases (e.g., Yoshi!) and to safeguard the safety of the athletes (e.g., in ne-waza to free the athlete’s head from the judogi which prevents the evaluation of his physical state).