Hedge fund manager J. Ezra Merkin should not be held liable to his investors for investing their money in Bernard L. Madoff’s massive Ponzi scheme, a federal judge in Manhattan ruled last week.

Southern District Judge Deborah A. Batts ruled on Friday in In re J. Ezra Merkin and Gabriel Capital Corp. Litigation, 08-cv-10922, a putative class action against Mr. Merkin and three of his hedge funds—known as the Ascot Fund, Gabriel Fund and Ariel Fund—that Mr. Merkin may have been imprudent in investing with Mr. Madoff but had not deceived investors.