Lawyers in settlement talks over Sumner Redstone competency lawsuit -sources

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April 5 (Reuters) - Lawyers for Viacom Inc Chairman Emeritus Sumner Redstone are in talks to settle a lawsuit challenging the 92-year-old media mogul's mental competency, people familiar with the situation said on Tuesday.

Depositions of Viacom Chief Executive Officer Philippe Dauman and Sumner Redstone's daughter Shari Redstone, which were scheduled for Tuesday and Wednesday, have been postponed, one of the sources said.

The case, brought by Redstone's ex-girlfriend Manuela Herzer, has raised questions about the billionaire businessman's role in decision-making at Viacom and CBS Corp, where he is the controlling shareholder. In February, Redstone stepped down as executive chair of both CBS and Viacom. A settlement would ease investor concerns about the repercussions of the litigation.

Herzer is challenging her removal last year as Redstone's healthcare agent in favor of Dauman, saying Redstone was not mentally competent to make that decision. Redstone's attorneys say he was fully aware of his actions.

Dauman was set to be deposed on Tuesday about conversations he had with Sumner Redstone on Oct. 8 and Nov. 3. Herzer was forced out of Redstone's home on Oct. 12, and Redstone replaced Dauman on his healthcare directive on Oct. 16.

(Reporting by Lisa Richwine in Los Angeles and Jessica Toonkel in New York, Anya George Tharakan in Bengaluru; Editing by Ted Kerr, Lisa Von Ahn and Jonathan Oatis)