The two companies began negotiations after Roche raised its offer price to $93 per share on Friday. Roche is trying to acquire the 44 percent of Genentech it does not already own.

"The new price was enough to get both sides to the table," said the source, who was not authorized to speak to the press.

Roche and Genentech declined to comment.

(Reporting by Jessica Hall; editing by Jeffrey Benkoe)

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