58 Pa. Code § 163.133
Before a horse is permitted to start, the stewards shall be satisfied that its published past performance, whether in races or workouts, is of sufficient number to enable the public to make a reasonable assessment of its capabilities and may require them as a condition of entry.
The provisions of this § 163.133 adopted December 23, 1977, effective December 24, 1977, 7 Pa.B. 3931.