Im learning options right now. Since someone who sells a call can cancel it by buying it back whenever he wants, does that mean that someone else you bought a call, can have his call cancelled?
If you buy 100 shares of IBM and two days later someone else buys 100 shares of IBM, do they ask for your shares back to sell to that guy? No, that person simply buys his own 100 shares in the market. You are not connected to any counterparty when you buy an option so no one can cancel it from you.