A combination of a knock-in option and a knock-out option. More specifically, a knock-in-knock-out (KIKO) option has two barriers: a knock-in barrier and a knock-out barrier. The option’s payoff gets activated once the knock-in barrier is breached. However, once the knock-out barrier is touched, the option deactivates and dies out (gets knocked out).

It’s worth noting that the option getting knocked out has nothing to do with whether it has been knocked-in or not. The knock-out barrier doesn’t cease to exist even when the option gets knocked-in.

KIKO options are generally classified as American KIKO options and partial KIKO options.