The head of Def Jam Records boasts an impressive artist roster, which includes rapper Kanye West and pop diva Mariah Carey.

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The famous producer co-founded Def Jam Records with rap mogul Russell Simmons, helping to popularize hip hop music with the Beastie Boys, LL Cool J, Public Enemy, and Run-D.

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Gilliam, a community organizer, is also partial to baggy jeans and Kangol caps and looks less like the leader of the free world than the latest signing of Def Jam Records.

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Reid, who helped make international stars out of Usher, Pink, OutKast and Toni Braxton on LaFace Records and then helped resurrect the career of Mariah Carey and signed Justin Beiber to Island Def Jam, is currently the head of Epic Records.

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Labels included under the Universal umbrella are Def Jam, Motown, Decca, Island Records, Interscope Records and Polydor Records.

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