Simons also played his chips, taking up positions in MasterCard and competitor Visa, while closing out his position in American Express.

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At some later date--either when you feel like closing out the position or when the lender wants the shares sent back--you have to buy some shares and replace what you borrowed.

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While we engaged in numerous partial sales before finally closing out that AAPL position in December 1999, our average gain topped 200%.

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But keep in mind that closing out an options position in a piecemeal fashion like this will incur additional transaction costs and impact potential returns.

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As I have discussed in the past I favor closing out part of any position when I can get a decent profit in a relatively short period of time.

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Western Refining ( WNR - news - people ): The crude oil refiner popped up on our scanners this morning after one investor first took profits off the table by closing out a previously established long call position, and next extended bullish sentiment on Western Refining.

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In the years following this bad bet, the investor has dramatically pared back his stake in oil producers, most recently closing out his Exxon Mobil (XOM) position entirely.

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