>Ireland's corporate tax rate is 12.5% but drops to 6.25% if it's qualified R&D and IP income with an added 35% R&D tax credit.

Or to 0.005% if you're Apple.

>The Commission's investigation concluded that Ireland granted illegal tax benefits to Apple, which enabled it to pay substantially less tax than other businesses over many years. In fact, this selective treatment allowed Apple to pay an effective corporate tax rate of 1 per cent on its European profits in 2003 down to 0.005 per cent in 2014.