Never actually done this in the real world and have read conflicting data online. Could not find definitive language either. But lets say you sold naked a bunch of puts at the strike of $20 with an expiration nearly 2 years from now. It is then announced that the company is being bought and taken private for a price of $25 per share and this deal is expected to close in 6 months, well before the expiration of your short put position. What happens to your position? Seems a little too good to be true that you would pocket the whole premium.
1. Pat yourself on the back 2. Wait until you can buy them back for .05 3. Move on to next trade (free up your margin)
Similar question: what happened with RIMM options? TradeMonster paper account just sold/bought them at $0.00.
there's always the risk the deal fails, so your options might carry a value even if they are worthless intrinsically at the moment. Take your profits, move on.