> For the complete documentation index, see [llms.txt](https://eako-capital.gitbook.io/eako-user-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://eako-capital.gitbook.io/eako-user-guide/variations-on-barrier-options/knock-in-european-knock-out.md).

# Knock-In European Knock-Out

A Knock-In European Knock-Out is a European Knock-Out option that becomes active (is "knocked-in") only if the underlying spot breaches a predetermined barrier at any time before expiry.

The European Knock-Out barrier is valid only at maturity.