Computer maker Hewlett Packard (HP) has filed a lawsuit against its former head Mark Hurd in an attempt to stop him joining database software maker Oracle.
Oracle announced the appointment of Mr Hurd as co-president late on Monday night.
HP said Mr Hurd's appointment would put its "most valuable trade secrets and confidential information in peril".
Mr Hurd, who resigned from HP only a month ago, is a friend of Oracle's chief executive, Larry Ellison.
Mr Hurd was forced to quit after a sexual harassment investigation. He denies any wrongdoing and was backed throughout the investigation by Mr Ellison.
The two are among the best-known figures in the technology industry.
BBC News
