Stock Options Trading

Understanding Market Manipulation at Options Expiration

Market makers are generally short current month at-the-money options (both puts and calls) while the general public is typically (on balance) long those options. Market makers enjoy special margin requirements (or more precisely, a lack of requirements) that allow them to be short options without posting collateral that is required for ordinary investors. If a stock ends up exactly at a strike price at expiration, the market makers can keep their entire gains from both puts and calls that they sold earlier.

Obviously, they have a vested interest to do what they can to manipulate the stock price to end up precisely at a strike price.
For many years, this phenomenon has been tracked by many investors who are looking for a clue as to which strike price the floor will shoot for at expiration. The concept is called the Maximum Pain Indicator.

One free site where you can follow the indicator is Option Pain Here is what they say about it - "On option expiration days, the underlying stock price often moves toward a point that brings maximum loss to option buyers. This specific price, calculated based on all outstanding options in the market, is called Option Pain. Option Pain is a proxy for the stock price manipulation target by the option selling group."

For many years, I followed this indicator each month, and often it was right on the target (last month it was absolutely dead on SPY, for example). However, I have not followed it recently for several reasons. First, the indicator sometimes misses badly, and if you follow it closely, you will probably start placing large bets on its accuracy, and end up losing your shirt. I have preferred taking the position that I have no idea of where the stock will end up, as that is most always the truth.

Second, the indicator works best with individual stocks that are easier for the floor to manipulate than it does for broad-based ETFs like those we use in our portfolios.

Third, the change to strikes at dollar increments reduces the significance of the measure. Back when most strike prices were $5 apart, it was more important to have an idea where the stock was most likely to end up at expiration.

And finally, going into expiration week, the highest total of short puts and calls is almost always at the at-the-money strike price. This doesn't really tell you much except to expect no change in the stock price (which we know is usually not the case).

In spite of all these objections, it remains an interesting concept, and should probably be consulted just in case there is a strong indication that the maximum pain point is a few points higher or lower than the existing stock price.