Dre tops rap 'rich list' on Apple-Beats deal

Jessica Morris, Special to CNBC.com

Apple's $3-billion acquisition of Beats earlier this year helped co-founder Dr. Dre jump to the top of Forbes' Hip-Hop Cash Kings list – but a hefty tax bill means he's not a billionaire just yet.

Prior to the acquisition, a famous – and now deleted - video featured singer-songwriter Tyrese Gibson describe Dr. Dre – whose real name is Andre Romelle Young - as "the first billionaire in hip-hop right here".

Dr. Dre
Elsa | Getty Images

But although he's not quite there, pre-tax earnings of $620 million mean he's well on his way. His sizeable fortune outstripped that of all remaining 24 "Cash Kings" combined.

With $60 million each, Jay-Z and P-Diddy took joint second place, but were left trailing behind the Beats co-founder.

Shrewd businessmen Jay-Z has an impressive portfolio, which includes the Roc Nation entertainment empire, a stash of concert dates, his D'Usse Cognac costing around $50 a bottle and new album Magna Carta Holy Grail.

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An agreement with Diageo's Ciroc vodka drove most of the earnings of P Diddy – real name Sean Combs - which also got a boost from DeLeon tequila, Blue Flame marketing agency, Sean Jean clothing and Revolt TV.

Canadian rapper and songwriter Drake came in fourth place with an impressive $33 million. His album Nothing Was The Same, an arena tour and endorsement deal with Nike's Jordan line meant his earnings tripled in a year.

Macklemore and Ryan Lewis, who took the title of Best New Artist at this year's grammy awards, came fifth after amassing earnings of $32 million.

Other rich rappers include Kanye West in sixth place ($30 million), Cash Money co-chief Birdman in seventh place ($24 million) and Lil Wayne ($23 million) in eighth place.