David Neubert says yes, if you vote your conscience on the proxy card.
And believe it or not, your shareholder vote may very well make a greater difference than the votes of institutional investors. Most company boards realize that individual investors tend to be more enduring in their views and a whole lot more loyal, making them more desirable shareholders than fickle institutions. If an individual voices an opinion at a shareholder meeting or writes a letter, corporations recognize that there are likely thousands of others just like them and they listen.
Felix Salmon is highly skeptical:
If you consider yourself an ethical investor and you care about global warming, then it’s really hard to justify an investment in Valero, a company which is spending millions of dollars trying to repeal one of the few U.S. laws which takes global warming seriously. Certainly the diversification benefits of owning Valero stock aren’t in themselves sufficient to offset the fact that you, as a shareholder, are ultimately responsible for Valero’s expenditures on the Prop 23 campaign.