A World Anti-Doping Agency report has concluded that seven tennis players were cleared of doping offences on "clearly unsustainable grounds".
Bohdan Ulihrach and six other unnamed players were cleared
The ATP exonerated the players, who tested positive for nandrolone, after it could not prove the steroid did not come from electrolytes it distributed.
But Wada said: "It is clear that the source is not the electrolyte."
Greg Rusedski became the eighth player to be cleared, but his case was not covered by the Wada report.
Rusedski was cleared because his positive sample carried the same analytical fingerprint as the other seven cases as well as more than 30 other samples with higher than normal levels of nandrolone.
But though the ATP has withdrawn the suspect supplements, there have been more samples with the same analytical fingerprint since.
"There are now seven cases where exonerations were granted on what are now clearly unsustainable grounds and the exonerations may not be able to be revisited," said the Wada report.
Wada has no right of appeal in any of the cases because the ATP has not accepted Wada's anti-doping code.
Under the code, athletes are responsible for any substance in their bodies under the "strict liability" principle.
Wada said the independent tribunals which exonerated the players made an "extraordinary series of findings".
They were founded on two principles - shifting the onus of proof to the ATP to show
it was not the source of the positive tests, and precluding the ATP from sanctioning players because it might have been responsible for the positive tests.
The name of only one of the seven players, Bohdan Ulihrach of the Czech Republic, was made public.
He was banned for two years by the ATP but exonerated at a second hearing.