Do pre-market notifications and stock volatility trigger circuit breakers? Evidence from Turkish post-IPO stocks

• This paper combines pre-market notifications with firm-level data to analyze circuit breaker triggers in post-IPO stocks. • Pre-market notifications significantly increase the likelihood of intraday trading halts in newly listed Turkish stocks. • The impact of pre-market notifications is amplified by unexpected stock-level volatility. Understanding how the arrival of pre-market information triggers intraday circuit breakers in post-IPO stocks is central to analyzing market behavior in emerging markets, where information asymmetry and heightened volatility are common. Using data on newly listed stocks from the Turkish stock exchange, this paper examines the drivers of circuit breaker activations in the first year following IPOs. We find that pre-market notifications significantly increase the likelihood of a trading halt, with the magnitude of this effect being moderated by stock-level volatility. Our findings have important policy implications for assessing how pre-market disclosures interact with volatility thresholds to prevent unintended trading halts in fragile market environments.