Sport's highest court has been asked to provide a definitive ruling on the International Olympic Committee's eligibility regulation for doping offenders.
The Court of Arbitration for Sport was asked to determine the validity of a rule which bars any athlete receiving a doping sanction of greater than six months from competing at the next Olympic Games.
The International and US Olympic committees requested the ruling and the IOC Director General says it would erase any confusion ahead of next year's Olympics.
Dozen of athletes, including U.S. Olympic 400 metres champion LaShawn Merritt, could have their eligibility for the London Olympics affected by the rule.
Merritt received a 21-month suspension after testing positive in 2009 and 2010 for a banned substance.
His ban ends in July but under the IOC rule he would be ineligible to compete in London.