Assuming that everything is on the up and up, (that is to say, the managment isn't stealing from the stockholders) we can trust corporations to pursue their prime directive which is to increase the value of their holdings.
We can pretty much assume that they will do so regardless of how their actions effect the society as a whole, too.
That is their job, and I do not fault them for doing so, either.
It is up to US, and our government officials, to see to it that corporations zeal to advance their net worth does not lead to outcomes that cause problems for the society at large.
Of course, we too often find that instead of our government protecting society as a while, it is pandering to the needs of those corporations.
This is what happens when our SCOTUS decides that corporations have civil rights and that money = free speech, folks.
Corporations (some of them) have enormous power, and they can live (theorectically) forever.
So naturally, in the longer run, their influence over society far exceeds their value to that society.