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What Stocks got Pinned Today?

|Includes: BAC, BIDU, C, CAT, DISH, FSLR, GLD, Alphabet, Inc. Cl C (GOOG), IBM, JPM, MA, MCD, PFE, WFC

Often on Expiration Friday, you will find that certain stocks, indices, & ETFs get basically "stuck" around a certain round level that corresponds to an option strike price.

Why does this occur?  Well, there are a variety of factors ... and it is not usually just comprised of pure "market manipulation" as many think.

If a stock is lingering around a strike price, the expiring open interest there (especially if it is sizeable) may cause market makers to constantly be buying and selling around that level, esentially causing the stock to get pinned.  This is because market makers are usually hedging their delta (and gamma), and their front month option greeks will be changing as a stock osciallates around a strike price.

Another factor is that there may be a great deal of options trading hands around that strike price, which then causes the market makers to hedge with stock trades, as well.  There also is the psychological factor that traders and stocks are often drawn to "round" numbers such as strike prices, and there will be a significant number of buyers and sellers around that number, for example.  Also, many of these round areas are important from a technical perspective and may be the location of important resistance or support.

With that in mind, there certainly is a "pinning effect" that is often seen on Expiration Fridays.  This may be option related and may be "released" from the shares on Monday (but that is certainly not guaranteed).  Taking a quick scan of stock screens, here are some that jump out at me today that ended very close to strike prices:

Google (NASDAQ:GOOG) - 430 strike
Citigroup (NYSE:C)- 3 strike
Pfizer (NYSE:PFE) - 15 strike
Bank of America (NYSE:BAC) - 13 strike
Caterpillar (NYSE:CAT) - 34 strike
Yahoo (YHOO) - 17 strike
Baidu (NASDAQ:BIDU) -320 strike
Dish Network (NASDAQ:DISH) - 16 strike
First Solar (NASDAQ:FSLR) - 145 strike
SPDR Gold (NYSEARCA:GLD) - 92 strike
Mastercard (NYSE:MA) - 180 strike
Wells Fargo (NYSE:WFC) - 25 strike
IBM (NYSE:IBM) - 115 strike
McDonalds (NYSE:MCD) - 57.5 strike
JP Morgan (NYSE:JPM) - 37  strike