NEW YORK (Bloomberg) ? Devon Energy Corp., the biggest independent oil and natural-gas producer in the US, said it signed a contract with Bermuda-based SeaDrill Ltd. for use of a new semi- submersible deepwater rig in the Gulf of Mexico.

The four-year contract for the West Sirius rig is worth about $690 million and has options to extend the duration to five or six years, Oklahoma City-based Devon said in a statement. The rig can drill in up to 10,000 feet of water.

SeaDrill, a Norwegian oil-rig maker with headquarters in Bermuda, announced the contract for the rig on September 7 without saying who hired it. The rig is under construction in Singapore and due for delivery in the second quarter of 2008.

WASHINGTON (Bloomberg) An appeals court revived Schering AG's patent-infringement suit against Bermuda-based Tyco International Ltd.'s health-care unit over tools used in magnetic resonance imaging.

Schering's Medrad unit sued in 2001 in Pittsburgh, claiming Tyco Healthcare and Japan's Nemoto Kyorindo Co. infringed its patent. A judge threw out the suit, saying the patent was invalid because Medrad made inappropriate changes to have it re-issued.

The US patent appeals court in Washington overturned that finding. The changes were "the type of defect that can be corrected" under federal law, the appeals court said, sending the case back to the lower court for further proceedings.

MOSCOW (Bloomberg) ? UFG Asset Management, a Moscow-based investment firm with about $1 billion under management, will next month start the UFG Russia Alternative Fund to invest in companies that haven't gone public.

UFG Russia Alternative will start on November 1 with between $20 million and $25 million in capital and will aim to attract up to $150 million from investors, said Florian Fenner, UFG managing director. It will invest in retail, banking and consumer-goods companies, as well as in producers of raw materials outside the oil industry.

Russia Alternative will be managed by Fenner, 35, as well as Svetlana LeGall, 35 and Timur Salikov, 24. UFG Asset Management consists of UFG Advisors Inc., a Bermuda-registered company that owns UFG Invest, which is licensed in Russia.