The Ospreys have partially succeeded in appealing a points deduction imposed on them for failing to fulfil a rescheduled Magners League fixture.
Although the four-point penalty still stands, it has now been suspended for two years rather than applying with immediate effect this term.
But a £100,000 (€120,000) fine imposed on the Welsh region remains.
Celtic Rugby brought charges against the Ospreys in May, when an independent disciplinary panel found Ospreys had acted in breach of tournament rules and were guilty of misconduct.
It related to their failure to fulfil a rescheduled match against Ulster in Belfast in March. Ospreys claimed they did not have sufficient front-row cover, and the game was eventually played on April 13.
Ospreys appealed the punishment, and a Celtic Rugby disciplinary appeal committee, chaired by Edwin Glasgow QC, met in London earlier this week.
The appeal committee’s decision is final, and there is no further right of appeal for either party.