Alfred Thornton and Company Solicitors had the judgment registered against him earlier this month. The amount in question is €115,804.
The firm represented Mr Fingleton in a case where Ulster Bank was pursuing him, a disgraced former Fianna Fáil senator, and their two development partners, for a €13.2m land loan.
Mr Fingleton, of Liskillen, Abingdon Park, Shankill, Co Dublin, was described in the judgment as a retired businessman.
The 76-year-old left the Irish Nationwide Building Society (INBS) in April 2009. The organisation was nationalised in 2010 with debts of €5.4bn. It was later liquidated.
A report prepared for a sub-committee of the INBS, and given to the Public Accounts Committee, has previously shown that in 2007 INBS transferred €27.6m to Mr Fingleton’s private pension plan in January 2007.
Alfred Thornton represented Mr Fingleton in the case taken by Ulster Bank in 2010. This centred on a €13.2m loan Ulster Bank advanced to Mr Fingleton and his three development partners to buy a 50-acre site in Cavan.
His partners in this deal included the then Fianna Fáil senator, Francis O’Brien, and two other developers, Noel Mulligan and Charles McGuinness.
The borrowing was approved by Ulster Bank in 2006 on a rolled-up interest rate, but it was not repaid when demand letters were issued. When this case went to the Commercial Court, Mr Justice Peter Kelly said it was extraordinary that Mr Fingleton’s €27.6m pension pot was not included in his statement of assets.