By Yifan Wang

Shares of Ningxia Building Materials Group Co. and Shanghai Xinhua Media Co. fell sharply on Friday, after the companies said that they didn’t have substantial business involvement in conversational artificial-intelligence technologies.

In the first four sessions this week, shares of Ningxia Building Materials had surged 46% while Shanghai Xinhua Media gained 24% but were down 10% and 9.3%, respectively, in Friday’s morning session.
Shares were lifted this week by the market’s enthusiasm for artificial intelligence plays after heavy media coverage of ChatGPT, an artificial-intelligence chatbot developed by San Francisco-based AI research company OpenAI.
Friday’s drop came after stock exchange filings by Ningxia Building Materials and Shanghai Xinhua late Thursday said they don’t have substantial revenue contributions from or material stakeholdings in AI-related operations.
Investors had snapped up shares of Ningxia Building Materials, which primarily produces and sells cement, because it has proposed a merger with a Microsoft distribution partner. Microsoft last week launch a new version of its Bing search engine with integrated ChatGPT technologies.
Shanghai Xinhua Media, a media publishing firm, had attracted investors interested in the AI field because of its holdings in a big-data translation service provider.
Write to Yifan Wang at yifan.wang@wsj.com