There are companies that offer you the possibility to short Bitcoin.
They own or buy bitcoins which you can lend from them. You pay an interest for that.
But you have to ask yourself if that would be wise. Bitcoin doesn't trade like a stock.
It isn't acting on results, it's usage will be growing, and it is more likely to move up more then down.
If you short normally you do it expecting that it might help bring it down further, to buy back lower. With bitcoin, after a large sale, it almost always bounces up again, making your short starting with a loss.
If you want to short on upcoming news, ask yourself what news would that be? It isn't like with a normal company, no insider information, everything is public. BTC isn't depending on just one company, it is trading on the usage worldwide.
So in my opinion, shorting bitcoin is very stupid. Due to the large usage volume worldwide you need a lot of money to cause panic sales, abd even then your gain will be very small!
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