PARIS--A French appeals court Monday partly overturned a 2011 ruling that found former Vivendi SA chief executive Jean-Marie Messier guilty of criminal charges related to the media conglomerate's near-bankruptcy in 2002.

The Paris appeals court upheld a conviction for embezzlement in relation to his severance package when he left the top job at Vivendi. The court, however, reduced the conviction to a 50,000-euro (68,470) fine and 10-month suspended prison sentence, down from a EUR150,000 fine and a three-year suspended prison term.

The appeals court also dismissed an earlier conviction that Mr. Messier had mislead investors during his tenure as the company's CEO.

"This ruling puts an end to the legend saying Vivendi was badly managed," said Mr. Messier's lawyer Francis Szpiner.

Mr. Szpiner said Mr. Messier would appeal the embezzlement ruling with France's highest court.

The appeals court decision comes 12 years after one of the most sensational corporate downfalls in recent European history.

In the late 1990s, Mr. Messier turned a stodgy water company called Cie. Generale des Eaux into Vivendi Universal, a trans-Atlantic media giant through a series of acquisitions. Mr. Messier's appetite for acquisitions weighed on Vivendi's balance sheet, however.

By June 2002, the CEO was forced out as the firm struggled with about EUR20 billion of debt. Prosecutors launched a criminal investigation soon after.

In the 2011 verdict, a three-judge panel upheld prosecutors' arguments that Mr. Messier misled investors with statements about the company's financial health in a series of newspaper interviews and public declarations. The panel however, cleared Mr. Messier of the charge that he allegedly manipulated Vivendi's share price with buybacks of stock in 2001.

Mr Messier has since embarked on a new career with an investment advisory firm Messier Maris Associés.

Write to Inti Landauro at inti.landauro@wsj.com and Ruth Bender at ruth.bender@wsj.com

05-19-14 0903ET

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