Arthur J Gallagher & Co

Marsh & McLennan shares fell 0.71% as the company filed for a senior notes offering and registered shares for employee awards, while insurance brokers face ongoing concerns about AI disruption.

Aon shares rebounded 3.1% after Monday's sharp decline triggered by an AI-powered insurance comparison tool. The market is assessing whether such technology could pressure traditional broker fees.

Emergency crews responded to an incident at Valero Energy's Port Arthur refinery Monday evening, with reports of flames and smoke. The facility processes 435,000 barrels daily, making any extended outage significant for fuel supplies.