Generally speaking, making business in stock market, dealing in shares or investing in a company is no problem provided it is done according to the correct shar`i contracts. But, if a credit or loan is involved so that it entails interest (ribaa), such a dealing does not enjoy any shar`i justification.
You do not own the income you earned through binary option by obligatory caution.
According to some experts, there are two groups of brokers in forex market:
The first group, which include most of the individuals who claim brokerage, just create an internet page and are not really available in the foreign exchange market. Such brokers receive money from clients to spend it for their own works and goals and just create an internet page for the client in which it seems that the client deals in foreign exchange transactions. Therefore, the transactions done like that are unrealistic and void and one does not own the resulting income.
The second group are real brokers who really attend in the foreign exchange market and deal in foreign currency with the client money. Such a transaction is no problem by itself provided that it is done observing its shar`i and legal standards. Anyhow, one should notice the following points:
1- Transactions should be real in which real currency is being sold and bought. Therefore, if the income is gained on the basis of forecasting currency value fluctuation, it is not lawful.
2- If the transactions, which are done by taking credit from the broker, have the nature of taking loan on interest basis, it is riba and haraam.