Since the ESMA changes all retail clients must be offered negative balance protection.
This means that a retail traders account cannot go into negative equity.
In other words, a retail trader cannot lose more than the value of their account and end up owning their broker money.
It’s actually a sensible move by ESMA, as during Black Swan events like the CHF cap removal some inexperienced traders were left owing hundreds of thousands of pounds.
However, if as an experienced trader you opt to upgrade your account to professional status (you can compare professional trading accounts here) negative balance protection no longer applies.
This means if you have a pro account it is possible to lose more than the value of your account and end up owning your broker money.