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Hedge fund firm Tudor Investment closes oldest fund: source

Paul Tudor Jones, founder and chief investment officer of Tudor Investment Corporation, speaks at the Sohn Investment Conference in New York, May 5, 2014. REUTERS/Eduardo Munoz

NEW YORK (Reuters) - Paul Tudor Jones, the founder and chief investment officer of the roughly $13 billion hedge fund firm Tudor Investment Corp, has closed his firm's oldest fund, a source familiar with the matter said on Monday.

Jones announced in a letter to investors in mid-December that his firm planned to return the $300 million Tudor Futures Fund's cash to investors by the end of 2014, according to the source, who asked not to be identified because the information is private.

The fund, which Jones ran after launching it in 1984, posted investment gains in every year since its inception, the source said.

The source declined to provide details on the reasoning behind the Greenwich, Connecticut-based firm's decision to close the fund.

(Reporting by Sam Forgione; Editing by Leslie Adler)