This question relates to the Kospi 200 index options for Aug expiry, which expired yesterday at the close 14:50 Korea time. I got completely reamed ... wondering if someone could shed some light, beyond the obvious. The gist: Stock and stock index options ceased trading at 14:50 local time. The index appeared to close around 204.55, and futures were trading near that level. Yet the Korean Exchange has set the settle price at 202.46, an almost 1% fall in a rising market. WTF happened here? Pls keep the snarky comments to a minimum guys, I'm looking for real understanding.