Quote from optioncoach:
The quick and dirty answer is that the index options are skewed such that OTM calls have lower IV than the ATM calls and OTM puts have lower IV than the ATM puts.
For puts it is a result of market crashes in the past. Large institutions and traders purchase OTM puts as insurance on large stock portfolios and market makers know that these OTM puts always have buying demand due to fear of a crash which could happen at anytime. This buying bias pushes prices up and skews the vols in the OTM puts.
Large players also sell covered calls against their stock portfolios for added income and slight hegde protection. This selling bias pushes OTM call prices down and skews vols lower.
This is the vanilla reason and these skews will always be there and are not really telling us anything but reflect a current behaviour in the market. if the OTM calls moved up in price, then more people would sell them against their stock portfolios, pushing them backlower. If OTM puts got relatively cheaper, then more players would buy up the cheap OTM insurance, pushing the prices back higher. So the market keeps the skew in place.
Thank you. The call IVs for Nov are extremely low - at 8.x %. Absolutely no premiums here, I guess. So aren't call sellers at a big disadvantage - given the recent move of the markets ie not being compensated enough for the risk taken?

