[cwkoss]

Your approach requires that the market makes knowledge about endangered-species-killing-companies available.

I can't think of a single company off the top of my head that is a 'known endangered species killer' so I'd suspect the mechanism you suggest does not actually function.

[padobson]

A good rule of thumb is that if something is good, the market will support it. The "information asymmetry" argument is typically a red herring.

No legislation will stop species extermination if information about the extermination is unattainable. If it's not available to activists and competitors, it's not available to regulators.

If the information is attainable, then the aforementioned activists and competing companies are both incentivized, morally and financially, to find it.