I found this interesting : " A Double Irish Arrangement " Tax info...

A Double Irish Arrangement is a strategy that lets US corporations pay a
12.5% Irish tax instead of a 35% US tax.

A Double Irish Arrangement is a tax strategy that allows corporations that
are not located in Ireland to take advantage of the country's 12.5%
corporate tax rate. This strategy is accomplished by a company setting up a
corporate subsidiary, or a smaller company controlled by the primary
corporation, in Ireland and selling the foreign rights to its products. The
subsidiary then sets up its headquarters in a tax haven. A second Irish
subsidiary is set up by the primary Irish subsidiary to receive profits.
According to Irish tax law, if a company is headquartered elsewhere, its
profits aren’t subject to Irish taxes. In the US, the tax rate for
corporations is generally about 35%.

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