The Central Bank has fined financial services provider Alico Life International a total of €3.2m.
This is for various breaches of the Insurance Act 1989 and the European Communities Framework Regulations 1994.
The fine is the third largest issued by the Central Bank, with Combines Insurance Company of Europe and Quinn Insurance having heavier fines imposed on them.
Alico is part of US group MetLife.
The Central Bank said the firm infringed a key regulatory requirement that receipts of the life assurance business must be entered into the life assurance fund. It also found evidence of serious inadequacies in the firm's systems and controls in that it failed to ensure that investment decisions were made and monitored in accordance with the firm's investment policy.
The breaches were discovered during an inspection in 2009, which led to an investigation by the Central Bank's enforcement division.
''The key principle of life assurance regulation is that policyholder assets are adequately safeguarded,'' commented the Central Bank's director of Enforcement Peter Oakes.
''It is for this reason that there are strict rules in place to ensure that policyholder assets are clearly identifiable from other assets of a life assurance company,'' he added.
In a statement issued by Alico Life International Limited, it says "we take the judgement very seriously and regret the deficiencies that the Central Bank of Ireland found. It is important to remember however that no policyholders were adversely impacted in anyway whatsoever. The issues raised are from some time ago and a new management team was appointed to address all of the areas of concern. All of the identified issues have been rectified and the company is in a strong position moving forward."