Sany Heavy Industry Co Ltd on Sept 10 denied a report that CNOOC had made the construction-equipment maker a new business partner to replace China Rongsheng Heavy Industries Group Ltd, whose chairman is the subject of an insider-trading allegation by the US authorities.

The 21st Century Business Herald had reported that Sany is negotiating with China National Offshore Oil Corp to provide the oil giant with maritime engineering equipment, research, development and manufacturing, citing the visit of Sany Chairman Liang Wen'gen to CNOOC in mid-August.

The replacement rumor gained traction after CNOOC's former partner, China Rongsheng, the country's largest private shipbuilder and an equipment provider to CNOOC, was involved in an insider-trading allegation that threatened CNOOC's largest overseas acquisition of Canadian oil company Nexen Inc.

In late July, the US Securities and Exchange Commission accused a Hong Kong-based company controlled by Zhang Zhirong, chairman and founder of China Rongsheng, of reaping more than $13 million from illegal trades ahead of CNOOC's announcement that it would buy Nexen Inc.

The SEC said businesses owned by Zhang, including China Rongsheng, have a close relationship with CNOOC.

The incident clouded CNOOC's purchase and was believed to have strained relationship between China Rongsheng and CNOOC.

But in its public statement, Sany said its chairman's visit was routine, and 21st Century Business Herald's report was not true.