The South Korean trading platform triggered the KOSPI index circuit breaker mechanism, suspending programmatic trading for 5 minutes

The South Korean trading platform (KRX) triggered the sidecar mechanism due to fluctuations in the KOSPI index, suspending programmatic trading for about 5 minutes.

The sidecar mechanism is mainly used to respond to severe fluctuations in a short period of time, limiting only programmatic trading while manual trading can continue normally. Unlike the circuit breaker mechanism, the sidecar mechanism does not suspend trading for the entire market and is more viewed as a "speed bump" during market volatility.

In contrast, the circuit breaker mechanism is typically used in extreme market conditions and, once triggered, suspends trading for the entire market to prevent panic-induced fluctuations from further escalating.