JP133 General.
2. Penalty faults include disobediences, falls, knockdowns and time penalties. No more than one penalty may be scored at each attempt.
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JP138 Knockdowns .
1. Definition. An obstacle is considered knocked down when in jumping an obstacle, a horse or rider, by contact:
a. changes any part thereof which establishes the height of the obstacle or the height of any element of a spread obstacle, even when the falling part is arrested in its fall by some other portion of the obstacle; or
b. moves any part thereof which establishes the height of the obstacle so that it rests on a different support from the one on which it was originally placed.
2. Special Circumstances. Should a pole resting in a cup come to rest on the lip of the cup, or on a bracket which is an integral part of the cup, it is not considered a knockdown. Narrowing the width of a spread obstacle without altering the height of any elements as defined above is not considered a knockdown. If, while in the process of being jumped, the top element is struck in such a fashion that it changes the height of the jump, with both ends remaining in the cups and nothing else supporting the top element, it is scored as no faults.