ANGLO Irish Bank is being sued by a former staff member over a bonus that was never paid.
The UK-based staff member had been due to receive bank shares as part of a bonus scheme, but this never happened after the troubled lender was nationalised.
The ex-employee, who worked in the bank's treasury division, has now taken an employment tribunal case against the bank in London, seeking a payment of £25,000 (€29,300) in lieu of the shares.
Evidence has already been heard in the case and a judge is expected to make a decision in the coming weeks.
If successful, the case could have major ramifications for Anglo, which may find itself exposed to a situation similar to that being experienced by AIB.
AIB is facing claims in the Irish courts from up to 100 staff in its capital markets unit for bonuses ranging from €3,000 to €100,000 after an employee successfully sued the bank over an unpaid bonus.
An Anglo source with knowledge of the UK case said that if the former staff member was successful, the bank could be exposed to claims from up to 500 staff members, totalling €13m.
But a spokeswoman for Anglo declined to speculate on the bank's possible exposure.
An Anglo spokeswoman said the bank "vigorously defended its position" in the case.
A number of Anglo staff in Ireland brought unsuccessful cases via the Rights Commissioner relating to similar bonus schemes, she added.
The former UK employee was due the shares as part of a cash-and-share bonus package included in a long-term investment plan open to staff.
The cash element was paid to the staff member, but no shares were assigned due to the bank's collapse.
The former employee is seeking a payment in place of the shares promised, but Anglo has argued it is under no obligation to make any such payment.
"The tribunal has yet to publish its decision and the bank will not comment in advance of its decision," the spokeswoman said.
"Anglo Irish Bank has made a decision that there is no basis for making any payment to a current or former staff member in lieu of an award under the long-term investment plan.
"The bank has to date, and will continue to, strongly defend this position in respect of this."
Finance Minister Brian Lenihan is planning to impose a 90pc tax on bankers' bonuses in the Finance Bill, which is due to be debated in the Oireachtas this week.
The move is being made to discourage staff members from taking legal actions over unpaid bank bonuses.
Other countries have introduced a specific tax on bank bonuses, but none have been as penal as what is proposed by Mr Lenihan.