Among other initiatives to encourage economic growth the OECD established a tax convention to prevent tax discrimination. We frequently quote it on UK tax returns when double taxation relief is an issue.
This year they tabled an initiative to stop tax competition between countries and to establish a minimum corporation tax rate of 15%. 130 countries representing more than 95% of the worlds GDP backed the deal.
Ireland has a rate appreciably below that agreed level. Apple and many other tech companies including air bnb process their sales through Ireland to take advantage of the lower rates.
That generates a of of tax revenue for Ireland and less for the countries where the economic activity takes place.
The EU is against competition, particularly tax competition. However they do allow lower rates for it’s smaller members.
Hence, Ireland, Hungary and Estonia are able to be EU members with low corporate tax rates. They have not agreed the OECD deal………yet.
Ultimately sanctions will be applied to those who don’t comply.