I would say investing in it makes you indeed at least partially responsible. Not investing isn't telling people what they shouldn't do. Of course people using

I would say investing in it makes you indeed at least partially responsible. Not investing isn't telling people what they shouldn't do. Of course people using fossil fuel take part of the blame as well, but responsibility for investments more than normal consumption by quite a margin. While others use the ressource, you have a profit incentive with its use and you also now have incentives to increase usage further.