Hedge fund star gives warning for road ahead

Citadel outperforms

Kenneth Griffin, whose Citadel hedge funds manage $24 billion in assets, said in a letter to investors Monday that he is approaching 2015 with "vigilance" in light of tumultuous market circumstances.

"Market conditions remain uncertain," wrote Griffin, founder and CEO of the Chicago-based money manager, in a letter dated Feb. 9. "A half-decade of unprecedented government intervention and monetary stimulus continues to impact the global financial markets."

"We continue to challenge our assumptions [and] assess our portfolio's risk," Griffin added in the letter.

He noted that despite the headwinds, Citadel Wellington, his firm's flagship fund, was up 2.73 percent in January—the reverse image of the , which fell more than 3 percent, and better than the average hedge fund, which was up fractionally, according to figures tracked by market-data provider HFR.