There is no such law, ChatBLT told me so.
But seriously, there isn’t because it so vague. Short term vs long term profits alone produces so much wiggle room that even if such a law existed it would be meaningless.
The term of the profit is of course a difficult matter of interpretation, but the charter is still profit, instead of e.g. ethics or benefits for mankind, on some time scale.
At least in Finnish law it's very plainly clear: "The purpose of a [limited liability] company is to make profit for shareholders, unless otherwise indicated in the bylaws."
("Yhtiön toiminnan tarkoituksena on tuottaa voittoa osakkeenomistajille, jollei yhtiöjärjestyksessä määrätä toisin." Osakeyhtiölaki, luku 1 pykälä 5)
Edit: For contrast, the purpose of universities (and thus, at least in theory, university researchers) is by law to "promote free research and scientific and cultural enlightenment, give highest education based on research and raise [their] students to serve the fatherland and mankind". [pardon for some awkward to translate phrases]
