It isn't marginable, what is meant is when the whole market goes down 200 points and the margin call comes in people will sell their gainers to pay that call whether the stock they sell is margined or not. Most investors will have more than 1 stock in their portfolio at a time. Some may be margined, some not, but they all sell for cash. (there is an exception, if your account is full of .000 bid stocks, you should not be trading on margin imo! )
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