John W. Henry to Stop Managing Client Money By GREGORY ZUCKERMAN John W. Henry & Co., a trading firm controlled by the principal owner of baseball's Boston Red Sox, told clients it will stop managing their money at yearend amid dwindling assets and slumping returns. John W. Henry, which managed more than $2.5 billion in 2006, today oversees less than $100 million, Mr. Henry said in an email. The firm will continue to do some trading for its own account. "The firm has been small since 2007 and once assets fell below $100 million this year the company became too small to sustain itself," Mr. Henry wrote. "We have been returning assets to investors with a desire to exit the client business by year end." John W. Henry is one of the best-known commodity trading advisers, or CTAs, which trade by following trends in various commodity, currency, debt and equity markets. The firm, a hedge-fund-like operation based in Boca Raton, Fla., scored big gains earlier in its existence, helping Mr. Henry's investment group buy the Red Sox. Mr. Henry hasn't had a hands-on role at the trading firm in recent years. Fenway Sports Group, the parent company that houses his sports interests, also owns the Red Sox's historic ballpark, Fenway Park, and Premier League stalwart Liverpool Football Club. Amy B. Hanson, a marketing manager for John W. Henry, sent an email to clients on Friday informing them that "JWH has determined to cease managing client assets" as of Dec. 31. "We will not be providing performance information going forward," Ms. Hanson wrote. That performance has faltered in recent years, slumping badly in 2012. The returns of Henry's five trading programs available for its investors have ranged from a loss of nearly 1% to a loss of over 21% this year, and a loss about 2% to a loss of about 32% over the past year, according to the firm. Two of John W. Henry's funds are each down more than 6% over the past three years, the firm said. Over five years, they are up 8.8% and 4.6%. "The current market environment of low volatility, where policy makers have been effective at managing prices, has proven especially challenging for trend-following trading strategies," Kenneth Webber, the firm's president and chief operating officer, wrote in a letter to clients in September entitled "Low Volatilty Creates a Challenge for Trend-Followers." In the letter, Mr. Webber said the firm suffered losses from grain trading and energy investments. "We appreciate the patience of our investors during this difficult period," Mr. Webber wrote at the time. The performance of Mr. Henry's firm, established in 1982, has long depended on long-term, distinct trends in various markets. The firm generally searches for markets that are making significant moves and jumps in, betting that they will continue. The choppy markets of recent years, and a relatively placid 2012, both have hurt. There have been few distinct, dramatic trends for these kinds of traders to pursue. Mr. Henry's firm has scored some gains in some of its trades, according to its most recent letter to investors, but they haven't been enough to offset losses. Clients, including many individual investors, had exited the firm even as many hedge funds enjoyed an influx of cash from investors. In 2007, for example, Merrill Lynch & Co. withdrew about $600 million of investments from Mr. Henry's firm. The move left the firm with about $500 million. At the time, Mr. Henry said: ""It's very painful, one never gets used to poor performance periods." The decision caps a rough year for Mr. Henry. His Red Sox finished in last place in the American League East during the 2012 season, 26 games behind their archrivals, the New York Yankees. Mr. Henry's soccer team, Liverpool, has also been struggling, despite a coaching change at the end of last season. Once the most-decorated club in England, Liverpool has won just two of 10 games this season and is mired in 12th place in the Premier League.