Gardaí are investigating changes made to loan documentation for some of the so-called Maple 10 by Anglo Irish Bank after the bank's share price tanked. The Maple 10 were customers of the bank who bought a 10% stake in the institution from businessman Sean Quinn in 2008.

Informed sources suggested the loan documentation was changed in some cases but not all. There is no suggestion of wrongdoing by any of the Maple 10, and the exact circumstances of the changes have yet to be established.

It emerged during a case taken by Paddy McKillen, one of the Maple 10, against Nama that the bank has no recourse to €40m it lent him to buy shares in the bank, with 25% of it initially being on a "recourse" basis.

McKillen's share purchase loan was reorganised afterwards, releasing him from the 25% of the loan for which he was personally liable. It has been reported that McKillen agreed to take part in the share transaction on the basis that he would not profit and the decision to release him from personal liability meant he did not lose out from the transaction either.

The bank placed 10% of its shares, which were held by Quinn, with the Maple 10 in July 2008.

After an initial rally, the shares tanked and the bank was eventually nationalised.

Meanwhile, former Anglo Irish Bank executives David Drumm, Sean FitzPatrick and Willie McAteer will find out in the next few weeks if they are to be disciplined by the Chartered Accountants Regulatory Board (Carb). The trio, along with former Irish Life & Permanent finance chief Peter Fitzpatrick, have been under investigation by Carb for more than 18 months. All four are chartered accountants.

The Sunday Tribune has learned that the Carb probe, led by former comptroller and auditor general John Purcell, will be completed next month. He is investigating the concealing of FitzPatrick's personal loans, the loans given to the so-called "golden circle" and the €7.4bn deposit switching transactions between Anglo and Irish Life.

Purcell's report will initially be submitted to Carb's disciplinary committee. If he finds evidence of any wrongdoing, the committee will recommend a formal disciplinary hearing to be held in public. Carb has the power to impose fines and a potential lifetime ban if any of the former executives are found to have breached Carb's rules.

Purcell is also probing the role of Anglo's former auditors Ernst & Young, though that report is not now due to be completed until early next year.

It is understood that more than 30 people have given statements under oath to Purcell and thousands of documents have been handed over to his inquiry.