Both the exchange and Interactive Brokers seem to use extremely dubious pricing of copper options. For example, the close in December Options was supposedly: 5.1 call .0065 5.2 call .0040 5.25 call .0030 5.3 call .0040 etc. Oh really! Of course they are just using the last trade for the close but should they do that? The reason for that 5.3 call being at .0040, a 60% increase over the prior close, is that some desperate person was actually bidding that amount, even though copper had just fallen sharply, I sold him the options at his price. Maybe I should have asked for .0050. The market in that month is very thin and it is practically impossible to get fills at reasonable prices. Also IB is currently marking these to, for example: 5.3 call .00753 Which is totally ridiculous since it was .0025 a few days when copper was higher. I know, volatility is higher, but not that much higher. I realize that the actual reason is that IB uses a (defective) pricing model for deferred month options. It does not cause me problems, but I am wondering if other commodity option pricing software is any better?