Options are only taxed when they are exercised. Say your option contract states that you can buy shares for €10. If the company’s value increases to €100 a share and you choose to exercise your option, you have to pay 50% income tax over the profit you make. In this case your profit per share is €90, so you would have to pay €45. If you then take into account that you paid €10 to exercise the option, you have made a profit of €35.