Ignore that last post, it's more complicated than I thought. If you write options and have a loss when they are repurchased, the 1099B, at least for E*Trade, shows a negative proceeds (negative of your profit) and a zero cost! Similarly, if you sell (write) options and they expire worthless, it will show of negative proceeds equal to minus what you got for them, and a zero cost. There is never a negative cost, afaikc.
