Some of the biggest and most respected names in the hedge fund industry are suffering through their worst-ever drawdowns.

Renaissance Technologies, the quantitative firm headed by James Simons, has seen its $18 billion Institutional Equities Fund drop 12% since it peaked in last May—its largest-ever maximum drawdown. Institutional Equities is down 6.64% this year, Bloomberg News reports, and has seen assets drop more than 14% due to the losses and client redemptions.

Another top firm seeing big losses since peaking is Traxis Partners, which has lost 15% since the end of September 2007. And Tiger Management veteran Stephen Mandel’s Lone Cedar Fund, managed by his Lone Pine Capital, is down 10.6% from its December 2007 high.

New York-based Satellite Asset Management’s Satellite Overseas Fund is also suffering, dropping 9.6% since the end of October 2007.