Rihanna told The Associated Press in a statement Wednesday that she's "so excited to take this next step in my career."
The 22-year-old is also launching a new company called Rihanna Entertainment. She says it will "merge all of her businesses, including music, film, fragrance fashion and book ventures."
Photos: Rihanna's Fashion Evolution
Jay-Z signed Rihanna to Def Jam in 2005. The two won a Grammy in 2008 for the hit song "Umbrella." Earlier this year, the pair picked up two Grammys for the rap song "Run This Town," which also featured Kanye West.
She's released four albums and plans to release her fifth CD, "Loud," on Nov. 16.
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