Payouts for third-party costs for the tribunal have so far amounted to nearly €10m, but the final figure is expected to be many multiples of this.
A string of companies, individuals, political parties, politicians and lawyers have demanded their costs and these claims are still to be settled.
The tribunal has had more than 400 witnesses. However, the fees for just 71 witnesses and their lawyers have been settled so far at a cost of €9.9m.
The tribunal argue that at least it has negotiated these downwards from a claims of over €14m.
The problem is there is no definitive final figure on what third-party costs may finally come to.
It is also likely that hearings on costs and claims may not be settled for years to come despite the release of the final report.
Judge Alan Mahon held public sittings for expense claims for months previously and claims that date back to 2002 have only been settled recently.
Some of these costs were only submitted to the tribunal after 2005.
The chairman has still to rule on costs for third parties for the years the tribunal sat after 2002.
The final estimate for the tribunal was put at €250m or more last week, which means that on top of its current overall cost of €97m, third-party costs could amount to over €100m or more when the final bills are done, according to previous estimates by the Comptroller & Auditor General.
Figures obtained by the Irish Examiner show that the largest expense claim so far was awarded to whistleblower and tribunal key witness James Gogarty, who received €3.56m. Just over €1m was granted to RTÉ in costs, while former finance chief with builders JMSE, Gerard Downes, was awarded €633,000.
Fianna Fáil PR guru PJ Mara was awarded part of his costs, despite having been found not to have cooperated with the tribunal. The former government press secretary and his wife Breda were granted €295,000 after submitting over €365,000 in claims.
Sums for legal and witness costs have also been paid out to Fine Gael (€215,000), Fianna Fáil (€483,000), Labour (€1,602), as well as several banks, including Anglo Irish Bank (€85,000) and National Irish Bank (€356,000).
Politicians who were awarded their costs include TDs Dermot Ahern (€294,000) and Tommy Broughan (€11,000).
Figures obtained from the Department of Environment show that individual third-party claims for 49 people amounted to €6.57m while corporate claims for 32 firms have amounted to €3.35m.
One of the reasons why third party costs could be higher relates to a 2010 Supreme Court case.
The ruling over the group JMSE reversed a decision in the High Court that JMSE was not entitled to its costs on the basis of the tribunal’s finding that they had obstructed the work of the tribunal. This ruling could set a precedent when it comes to claims against the tribunal which so far were decided on the basis of the final report’s findings.