Or, put another way, it would have been illegal for them to have paid that tax.
Directors have a responsibility to the corporation, they have no fiduciary responsibility to shareholders.
No shareholder would win a case against a corporation for 'paying too much tax' any more than they would win a case against a corporation for paying the directors or the CEO too much money.
This myth needs to die already.
Instead they're hoarding the money offshore in what looks like a figurative dragon in a cave hoarding shiny things. To my knowledge, hiding cash under your mattress has never been a wise investment strategy.
[1] Note: Plenty of other companies do this too. Apple, Microsoft, etc. all have played tax games, even just in the tech industry. Though I find the level of disparity between Google's public statements about how it thinks things should be, and the statements of employees who seem to think they improve humanity by working there, and the actual realities of Google's business operations bordering on the comical.
[Citation needed]