What Is “Pin Risk” in Options Trading?

Pin risk occurs when the price of the underlying asset closes exactly at or very near the strike price of an option at expiration. This creates uncertainty for the seller (writer) of the option, as they do not know whether they will be assigned the underlying shares.

If the option is a call, the writer doesn't know if they will have to sell their shares. This uncertainty makes it difficult to manage the position and can lead to unexpected losses or unwanted stock positions over the weekend.

How Do European-Style Options Reduce Pin Risk Compared to American-Style Options?
How Does Early Assignment Work for the Seller of an Option?
How Does the “Pin Risk” Phenomenon Relate to Basis Risk at Expiration?
What Is the Primary Risk for the Option Buyer versus the Option Seller?
What Is the Primary Risk Exposure for the Seller (Writer) of an Uncovered Call Option?
What Is ‘Short Selling’ an Option, and Why Does It Require Margin?
Is Time Decay Beneficial to the Option Buyer or the Option Seller?
How Does the Settlement Mechanism (Physical Vs. Cash) Affect Pin Risk?

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