Mobil Oil is the largest owner of solar panel technologies. If you want to build a solar panel, you will have to buy components from companies owned by Mobil or from companies who pay Mobil licensing fees to sell it...since Mobil bought up all the patents and such many years ago. They now sit on this and other technologies until such time as it economically benefits them to do otherwise.
This is more the type of thing I was alluding to.
The market for oil being what it is, it makes good business sense for companies to do this but given the current state of energy supplies and consuption it still seems a bit crass for them to do so.
Even if this were true, remember that a patent is valid for only 17 years.
Ah! I see your point. Trouble is, who is going to pay Exxon Mobil an extra 2 cents on the gallon to subsidise solar (which is barely profitable with tax rebates and subsidies)?