It’s not absurd. Microsoft believes they followed the law. The IRS doesn’t. If Microsoft believes they followed the law and then paid the bill they would now

It’s not absurd. Microsoft believes they followed the law. The IRS doesn’t. If Microsoft believes they followed the law and then paid the bill they would now be upholding their duty to shareholders. And to be clear, if they violated the law (should that be found in a final court case after appeals) then they will also have not done their duty for shareholders and also get sued. Your notion of Oxy is not at all relevant.