HONG KONG (AP) — A stock market filing says missing Chinese investment banker Bao Fan is co-operating in an investigation in China. China Renaissance Holdings Ltd., which Bao founded, gave no further details. The company says it has been unable to reach Bao but its operations continue as normal. The company’s Hong Kong-listed shares have slumped by nearly a third since Bao went missing. He is one of China’s top dealmakers in the technology industry, having worked on major deals including e-commerce company JD.com’s $2 billion initial public offering and the share listing for short video platform Kuaishou in Hong Kong. Bao’s whereabouts are unclear.