IGFA rules regarding leaders
Section D. Leader
The use of a leader is not required. If one is used, it must meet the following specifications:
The length of the leader is the overall length including any lure, hook arrangement or other device. The leader must be connected to the line with a snap, knot, splice, swivel or other device. Holding devices are prohibited. There are no regulations regarding the material or the strength of the leader.
Saltwater species: In all classes up to and including 20 lb (10kg), the leader shall be limited to 15 feet (4.57 meters). The combned length of the double line and leader shall not exceed 20 feet (6.1 meters).
The leader on all classes of tackle over 20 lbs (10 kg) shall be limited to 30 feet (9.14 meters). The combined length of the double line and leader shall not exceed 40 feet (12.19 meters).
Freshwater Species: The leader on all classes of tackle shall be limited to 6 feet (1.82 meters). The combined length of the double line and leader shall not exceed 10 feet (3.04 meters).