TORONTO - Navigating volatile markets will be the main challenge, said Ron Mock, who was named Tuesday to take over as president and chief executive of the Ontario Teachers' Pension Plan in January. Mock will replace Jim Leech, who is set to retire at the end of December after six years at the helm of one of Canada's largest pension funds. "We're the lead in defined benefits pension plan business globally, and I want us to stay there," he said Tuesday.

(Reuters) - Hess Corp offered hedge fund Elliott Management two seats on its board as the oil and gas company looks to avoid losing five seats to the activist investor at its annual meeting this week.

By Sarah N. Lynch and Andy Sullivan WASHINGTON (Reuters) - The researcher whose report prompted a spike in health stocks last month appears to have relied on lobbyists rather than U.S. government insiders who had direct knowledge of a pending healthcare decision, according to emails reviewed by Reuters. The messages could help bolster Height Securities LLC's claim that its analyst was essentially doing what reporters, lobbyists and others in Washington do every day: trying to figure out what the government is going to do next.

By Lawrence Hurley WASHINGTON (Reuters) - CBOE Holdings Inc <CBOE.O> won a long-running legal battle to prevent rival International Securities Exchange from listing options on two key U.S. stock-market indexes, after the U.S. Supreme Court on Monday declined to consider their dispute.