Below is my theory, that is false (because if it would be true then everybody would do it) but I do not know why:
If a stock price is being lowered by an amount that is paid as a dividend, does it mean that using CFD (sell) it is guaranteed to make a profit?
Why is this theory false?
Related: Does a stock really dip in price on the ex-dividend date? And why would it do this?
If you hold a short position CFD then you're liable for the dividend once the stock goes ex-dividend.
If the stock somehow does not drop the entirety of the dividend amount you'll make money, if it drops more you'll lose. On average it's going to drop the amount of the dividend.
Conversely if you're long on a CFD you receive the dividend (but the price of the stock itself will drop accordingly).
