Citizens United was explicitly about whether the state could categorize a documentary produced by one company (Citizens United’s Hillary the Movie) as regulated speech, vs documentaries produced by another company (Dog Eat Dog Film’s Fareinheit 911). In both cases there was evidence that the film was produced by a corporation whose shareholders and management explicitly intended to affect an election by engaging in political speech. It was a limit on the state’s capacity to limit one group of people’s speech rights and not another’s.

I agree that maximizing shareholder value is expected to be done within legal limits, but also basic ethical limits. I’m not an expert in Union Carbide’s history, but I was under the impression that the company was hollowed out after selling off assets to pay the Bhopal settlement, and Dow eventually acquired it along with its liabilities for a fraction of what its market cap would have been without the disaster. Criminal negligence can erase a huge amount of shareholder value.

In a different or malfunctioning legal system you could imagine the Indian courts not holding the shareholders responsible for their negligence, the way the US justice department failed to hold the financial industry responsible in 2008 for instance. Smarter people than I have pegged the rise of populist politics in the US as a delayed response to this political and legal failure to wipe out shareholders of corporations that took risks which harmed the economy.