Through her Harpo productions, Winfrey still has her hand in Dr. Phil, Rachael Ray and The Dr. Oz Show.

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She opened Harpo Studios in 1985 and Harpo Productions in 1988.

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The move will allow her to focus on her channel in development, OWN: The Oprah Winfrey Network, a joint venture between her Harpo Productions and Discovery Communications.

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Winfrey's Harpo Productions Inc. provided CNN with several preview clips.

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Madonna was speaking on The Oprah Winfrey show (Harpo Productions).

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Oprah Winfrey is a billionaire because of the value of her holdings in things like Discovery and Harpo Productions, not because of the ad revenue her show generated over the years.

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