The 82-year-old Sumner Redstone is chairman and chief executive of Viacom, while Shari, aged 50, heads up the National Amusements cinemas chain, which is the parent company through which Redstone Sr controls Viacom.
In June last year, Redstone said he planned to step down within the next three years. According to reports, he has repeatedly said that Shari, who was once a criminal defence attorney, would not have an operating role at the company although she has been on the Viacom board since 1994.
Viacom is due to hold a board meeting next week, where Shari Redstone's appointment is expected to be announced, according to a report in Variety.
Earlier this year, Viacom unveiled plans to split itself into two publicly traded companies, each under the control of one of the two current joint chief operating officers, Tom Freston, who heads MTV, and Les Moonves, head of CBS. This plan is due to be voted on at the meeting next week.
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