The International Cycling Union (UCI) is to appeal against a Spanish court's decision to destroy 200 blood bags presented as evidence in the trial of Eufemiano Fuentes.
Dr Fuentes, accused of running one of the world's largest sport doping rings, received a one-year suspended sentence.
On 29 April a Madrid court ruled the blood bags would not be released to the UCI and anti-doping organisations.
They want the bags tested to see whether they implicate other athletes.
Anti-doping authorities and international sports bodies have condemned Judge Julia Patricia Santamaria's decision to deny them access to the bags.
The World Anti-Doping Agency said the decision was "disappointing".
Fuentes was revealed by the Operation Puerto investigation to have been providing blood-doping services to cyclists.
When police raided his offices in 2006, they found 211 bags of frozen blood and plasma.
Fuentes has previously worked with tennis players, runners, footballers and boxers, although he has not said whether he helped them dope.