You relinquish your rights and realize a profit or loss based on the difference between your initial BTO premium and the current STC premium.
It can decrease or leave open interest unchanged, depending on whether the buyer is also opening or closing a position. buy to open sell to close
This order is used to a position you previously opened via BTO. When you execute an STC order: Action: You sell your existing contract to another party. You relinquish your rights and realize a profit
It typically increases open interest , as a new contract is often being created between you and a seller. Strategic Intent: buy to open sell to close
You pay a premium (debit) to a seller to acquire the rights of a contract. Result: You become the "holder" or "buyer" of the option.