The research team of U.S. stem cell expert Gerald Schatten has refused to comment on a recent report that he requested half of the patent rights to joint stem cell studies with South Korean researcher Hwang Woo-suk.

In a phone interview with Yonhap News Agency, one of Schatten’s team members made clear that a statement issued by the team on Friday would be the last, with no more statement or interviews to be made.

The local JoongAng Daily reported Monday that the University of Pittsburgh professor had requested the South Korean's team to cede 50 percent of the patent rights on their stem cell research.

Following the report, a member of Hwang’s team said he had never heard of such a request, adding that Hwang himself had never mentioned it either.

Government officials, including those from the Ministry of Science and Technology, also denied any knowledge about the alleged event.