By Christopher B. Welsh
I've had three emails in the past month on people being assigned on positions and receiving margin calls, and generally not knowing what happened. I advise everyone to completely research and become familiar with the exercise/assignment aspect of option trading. If you don't you can find your entire account blown out over a weekend.
Assignments occur in two basic varieties. First, on expiration Friday (or Thursday or Wednsday depending on the instrument your trading, but most commonly on Friday). If you have a position that is .01 in the money, or more, you WILL be assigned. For instance, if you have a 100 Call on stock XYZ that expires today, and XYZ closes (AFTER HOURS) at 100.01, you will find that you own, sometime Saturday, 100 shares of XYZ that you paid $100/share for.
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