Hey, your English is excellent.
When you say bank are you referring to your broker?
For retail shorting the margin requirements are too much to make it economically feasible.
The shorting is a myth on all pinkies.
The average investor can't or it is extremely difficult to short a penny stock - the margin requirements are just cost prohibitive. You have to have $2.50 margin per share to short a stock under $2.50.
If you want to short 500,000 shares of a stock at $0.004, you have to have $1,250,000 in your account, and 500,000 shares at $0.004 is only $2000.
The good thing is you won't get a margin call unless it gets over $2.50.
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