The notice was filed Monday to the Court of Arbitration for Sport, the international body that has the final say in such matters.
A U.S. arbitration panel earlier this month reduced the 25-year-old sprinter's potential eight-year ban to four, but Gatlin wants a further reduction.
He tested positive for excessive levels of testosterone at the Kansas Relays in 2006, his second doping offense. The first came in 2001 when Gatlin tested positive for amphetamines, part of a prescribed medication he was taking for attention deficit disorder.
Gatlin wants the first offense erased. That would make Gatlin's 2006 case his first offense, clearing the way for a further reduced ban. First doping offenses often result in a two-year ban, which would make him eligible to run in May, a month before the U.S. Olympic trials.
The appeal notice seeking a CAS hearing was filed by Gatlin's new attorney, Maurice Suh, who also represents cyclist Floyd Landis in his doping case.
"It's a right afforded to any athlete under our system," said U.S. Anti-Doping Agency CEO Travis Tygart.
In its ruling, the three-member panel unanimously agreed Gatlin committed a doping offense in 2006, but they expressed reservations about the 2001 finding, indicating it could be challenged.
However, that panel said it did not have the authority to rule on the 2001 case.
In that incident, Gatlin took medicine to help him study for an exam while a student at the University of Tennessee. Three days later, at the world junior championships, a small amount of the drug was detected in his system.
A different arbitration panel for that case found Gatlin did not use the drug to help his performance, and the international track federation reinstated Gatlin after one of year of what was to have been a two-year ban.
"To use this sanction to bar him from participating in the Olympics is a prime example of unfairness to an athlete," Suh said in a statement.
He called the four-year penalty "a grossly inappropriate balance of anti-doping efforts against the right of individuals to pursue their careers and their dreams and the right to receiver fair treatment by those in the sports system."
"Most troublingly, Suh added, "it constitutes a discrimination against a person with a diagnosed disability who was attempting to obtain education."
