How Do Brokers Differentiate Scalping From Short Term Trading?

It is a very thin line between scalping and short term trading. Generally if you hold trades for a minute or less, you may have problems with brokers. They could warn you and then if you continue shut down your account. However, if you trade in minutes or more, most likely you will not have problems with dealing desk brokers. Non dealing desk (ECN) brokers allow scalping where you can hold a position for seconds however the minimum to open an account is higher. ($2,000 and above).