a. All players shall be numbered 1 through 99. Any number preceded by zero is illegal.
b. On a scrimmage down, at least five offensive players on the scrimmage line shall be numbered 50 through 79.
c. No two players of the same team shall participate in the same down wearing identical numbers.
d. Markings in the vicinity of the numbers are not permitted.
Penalty: Live ball foul. Five yards from the previous spot.
e. Numbers shall not be changed during the game to deceive opponents.
Penalty: Live ball foul. Fifteen yards from the previous spot, and flagrant offenders shall be disqualified.