Public tariffs: The absence of this category, or the absence of a provision applicable to the fare in question, allows the fare to be ticketed immediately and without regard to where or by whom.
Private data: The absence of Category 15, or the absence of a Category 15 provision applicable to the fare in question, indicates that the sale of this fare is not permitted unless Category 35 provisions exist. Note: Security provisions must exist in either Cat 15 or 35 to use the fare.