The Ospreys are free to take their place in the knockout stages of the Heineken Cup after being cleared of fielding an ineligible player.
South African scrum-half Ricky Januarie's time with the Welsh region was the subject of a registration investigation by European Rugby Cup Ltd (ERC).
Januarie had joined the Ospreys from Cape Town-based Super 14 side the Stormers in November. He played in four HEC pool games but then returned to the Stormers, whose website had previously said he was moving to Wales on a two-month deal, while European Cup regulations state that a player 'must have at least a three-month contract with the club' to be eligible to play in the European competition.
Premier Rugby, the English Premiership clubs' umbrella body, lodged a complaint over the discrepancy, however at a specially convened board meeting in Dublin on Monday the ERC ruled that the Ospreys had no case to answer.
Ospreys managing director Roger Blyth said in a statement: "Having co-operated fully with ERC at all times during their investigation into this matter, and providing them with all the relevant paperwork relating to Ricky's contract and registration, we are delighted to have been informed that they have found that Ospreys Rugby has no case to answer.
"Now that we can finally put this matter behind us, we are, along with our many supporters, looking forward to our quarter-final against Biarritz in San Sebastian on Saturday, April 10."