IANAL, but I believe that you are correct, the corporation must pursue its shareholder interests for the purposes outlined in its articles of incorporation. That can be (afaik) any legal purpose. AMZN has repeatedly communicated their purpose of maximizing long-term shareholder value.
> AMZN has repeatedly communicated their purpose of maximizing long-term shareholder value
Even that doesn't pin them down. Amazon can easily say they believe it is in their own long term interests to campaign against patent laws and therefore sacrificing a small short term profit from the one-click patent is a logically correct way to maximize long term shareholder value. The argument that a company "has to do evil thing X" to maximize shareholder value is pretty much always just an excuse for avoiding argument about whether "thing X" is evil or not.
