SIX Swiss Practice Exam 2026 - Free Practice Questions and Study Guide

FOK and IOC are execution styles that demand immediate action on an order. With a Fill or Kill, the entire order must be filled right away at the chosen price; if any part cannot be filled immediately, the whole order is canceled. With Immediate or Cancel, any part that can be filled immediately is executed, and the remaining unfilled portion is canceled. Because these instructions require instant results, such orders do not sit as resting bids or offers in the order book.

That’s why the statement that they never appear in the order book is best. The other options don’t fit: they aren’t restricted to pre-market or to being not near continuous trading, and they aren’t simply standard limit orders—these are special, time‑sensitive execution rules.