A new study suggests that between 2017 and 2021, just three companies were responsible for one-third of all corporation tax collected in the Republic of Ireland.
That was estimated by the Irish Fiscal Advisory Council (IFAC) to be €5 point 2 billion (£4 point 46 billion) in 2021 alone and probably increased last year, external.
The tax that corporations pay is based on their profits.
Major US companies are choosing to pay tax on their international profits in Ireland due to changes to global regulations, which has resulted in a windfall for the country's corporation tax revenues.
Apple, which has claimed to be Ireland's largest taxpayer, is the most well-known of these.
Ireland collected €22.6 billion (£20 billion) in corporation tax last year, a 182% increase from the €8 billion (£7 point08 billion) it collected just five years prior.
Because of the enormous corporation tax revenues, the Irish government is able to maintain a budget surplus.
The government intends to use the extra money to create a sovereign wealth fund despite acknowledging that the windfall is probably unsustainable.
Based on publicly accessible data, such as submissions to Ireland's Companies Registration Office, the IFAC study.
It was discovered that in 2021, 34% of all corporation tax receipts were attributable to the top three companies.
Between 2017 and 2021, a five-year period, that share fluctuated between 30 and 38 percent.
These three groups' characteristics remained constant over the course of the period.
According to the study, the top 10 companies will pay over 90% of the corporation tax in 2021, with the pharmaceutical and IT industries being the main contributors.
Michael McGrath, Ireland's finance minister, tweeted in response to the study: "This level of concentration is a clear risk to our finances that cannot be ignored.
To make our finances more secure and sustainable, I'm creating ideas for a long-term savings fund.
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