"For instance, assume you short 100 shares of Big Co. when the stock is trading at $76.24. If the stock rises to $85 or beyond, you would be looking at a substantial loss on your short position. Therefore, you buy one call option contract on Big Co. with a strike price of $75 expiring a month from now. This $75 call is trading at $4, so it will cost you $400.

If Big Co. declines to $70 over the month, your gain of $624 on the short position ([$76.24 - $70] x 100) is reduced by the $400 cost of the call option, for a net gain of $224. We are assuming here that the $75 calls are trading at close to zero after a month. In reality, it may be possible to salvage some value from the calls if there are a considerable number of days left to expiry.

However, the real benefit of using a call to hedge your short position in Big Co. becomes evident when the stock rises instead of declining. If Big Co. advances to $85, the $75 calls would trade at a minimum of $10. Thus, the loss of $876 ([$76.24-$85] x 100) on your short position would be offset by the gain of $600 ([$10 - $4] x 100) on your long call position, for a net loss of $276.

Even if Big Co. soars to $100, the net loss will stay relatively unchanged at $276. The loss of $2,376 ([$76.24-$100] x 100) on the short position would be offset by a gain of $2,100 ([$25 - $4] x 100) on the long call position. That happens because the $75 calls would trade at a price of at least $25 if Big Co. hit $100."

https://www.investopedia.com/articles/active-trading/021715/how-protect-short-position-options.asp

Da ist es sehr gut erklärt.