A Madrid court has ordered hundreds of blood bags in the Operation Puerto case to be handed over to anti-doping authorities for investigation.
The doping scandal, which implicated more than 50 cyclists, could be reaching a resolution 10 years after the allegations came to light.
In 2006, police seized coded blood bags from the laboratory of sports doctor Eufemiano Fuentes, who was handed a suspended one-year prison sentence for improperly performing blood transfusions on athletes and endangering public health.
Today, a court acquitted Fuentes of the charges as the blood bags are not regarded as medicine and he has been given the green light to practise again.
During the lengthy legal battle, a judge ordered the destruction of the bags, but a number of bodies, including Spain's anti-doping agency, the International Cycling Union and the World Anti-Doping Agency, lodged an appeal to have the bags investigated.
The court has now ruled in their favour, allowing the blood bags to be re-examined by the Spanish Cycling Federation, WADA, the UCI and Italian Olympic Committee.
The allegations eventually resulted in the suspensions of cyclists Jan Ullrich, Alejandro Valverde and Ivan Basso.
In 2013, Fuentes told the court that he had worked with athletes from other sports, but the judge claimed that the names of the other sportspeople did not need to be revealed unless they were involved in the cycling case.