Knock-Out Option
Barrier option that terminates if the underlying asset reaches a specified level before expiration.
A knock-out option is a barrier option that terminates if the underlying asset reaches a specified barrier during the option’s life.
The contract is path-dependent. The final payoff depends not only on where the underlying finishes, but also on whether it touched the knock-out barrier along the way.
Barrier Mechanics
The diagram shows why the barrier matters. The option can disappear before expiration even if the underlying later moves back into a favorable range.
Common structures include:
| Structure | Barrier location | What happens |
|---|---|---|
| Up-and-out call | Barrier above the current price | The option terminates if the underlying rises to the barrier |
| Down-and-out put | Barrier below the current price | The option terminates if the underlying falls to the barrier |
| Up-and-out put | Barrier above the current price | The option terminates if an upside barrier is touched |
| Down-and-out call | Barrier below the current price | The option terminates if a downside barrier is touched |
Some contracts include a rebate if the barrier is triggered. Others simply expire worthless when knocked out.
Why It Matters
Knock-out options usually cost less than comparable plain-vanilla options because the buyer gives up protection or upside after the barrier is touched.
That lower premium is useful only if the barrier risk is acceptable. A trader can be right on the broad direction and still lose the contract because the path briefly touched the barrier.
Example
Suppose a trader buys an up-and-out call on a stock trading at 100:
- strike:
100 - knock-out barrier:
120 - expiration: three months
- rebate: none
If the stock touches 120 before expiration, the option terminates. If the stock later closes at 115, the trader no longer has a live option even though a plain call would have value.
Pricing And Risk Drivers
Important drivers include:
- distance between current price and barrier
- expected volatility and jump risk
- time to expiration
- monitoring frequency and official price source
- rebate amount, if any
- liquidity and whether the contract is OTC
- hedging difficulty near the barrier
Barrier monitoring is especially important. A contract observed continuously can knock out under conditions that a contract observed only at official fixes might survive.
Public Source Checks
- The OCC Options Disclosure Document is the key public disclosure source when the option is a standardized listed option cleared through OCC.
- FINRA’s options overview explains the general rights and obligations behind options, but exotic barriers require the actual contract terms.
- For an OTC barrier option, the controlling evidence is the term sheet, confirmation, valuation model, collateral agreement, and barrier-observation language.
Common Confusion
Do not assume “out” means the option is out of the money. In a knock-out option, “out” means the contract ceases to exist after the barrier event.
Related Terms
- Barrier Option: The broader barrier-option category.
- One-Touch Option: A path-dependent option that pays when a level is touched.
- OTC Options: Customized options where barrier language often appears.
- Vanilla Option: A standard option without barrier termination.
- Implied Volatility: A major input in barrier-option pricing.