Not all EU countries have the same tax rates so yes, it is allowed to have lower ones. It is OK to have low rates (like Slovakia and some other countries have)

Not all EU countries have the same tax rates so yes, it is allowed to have lower ones. It is OK to have low rates (like Slovakia and some other countries have) as long as the same rules apply to all companies. Problem with this one is that they didn't and it wasn't a loophole. It was a well understood and by Ireland supported ignorance of existing treaties which have an effect of a law that just finally caught up with them.