Sinn Fein MLAs who claimed almost £700,000 in expenses for research by a company run by the party have been cleared of any wrong-doing.
The Assembly Commission has also declared claims for payment of office rent to three apparent cultural societies were "admissable".
But TUV leader Jim Allister has blasted the verdicts - following allegations in a BBC Spotlight programme - as "bizarre".
He also asked the Commission, which is responsible for the day to day running of Parliament Buildings, how much of the expenses paid out had been recovered.
In a written response, the Commission said that, as the expenditure was admissable, no recovery was sought.
Mr Allister said: "The Assembly Commission has now confirmed that none of the £700,000 claimed by Sinn Fein MLAs and paid to Research Services Ireland has been recovered by the Assembly in spite of the BBC finding that no evidence of research carried out by the company could be produced."
He added: "It is remarkable that the Assembly would take such an attitude with taxpayers' money without explaining how they reached the view that the expenditure was admissible."