So, Dr. Dre isn't quite a billionaire; not yet.

Apple Inc. is, however, a $500 billion dollar company, and its recently confirmed acquisition of Beats Electronics will make Apple executives of Dre and former Interscope chief Jimmy Iovine, who together founded the Beats brand in 2006. (Dre will cash out with about $150-$250 million, according to Forbes' speculation of the payout structure and calculation of applicable taxes.) Both Dre and Iovine will report to Eddy Cue, Apple's senior vice president of Internet services. With Beats Music now entering the fray versus Spotify, Rdio, and Pandora, Dr. Dre will have a hand in the evolution of the music streaming economy.

For an O.G. gangsta rapper and producers, that leap from Compton to a Mountain View C-Suite is a mighty stride.

The past couple decades of hip hop have promoted multimedia and industrial conquest as rap's highest aspiration.

A global coup for hip hop branding. Some will cringe upon reading that very pairing of "brand" and "hip hop," especially in such a corporate sense, but in a genre built upon tales of the master plan and the big payback, this is the American Dream. While the annual jockeying for Hip Hop's Biggest Mogul is fascinating for a news cycle or two, the Forbes list is just a snapshot of the culture's business acumen, and the cultivation of legit capitalist hustle among hip hop's most ambitious tier.

Such growth has been a long time coming. After 1993, Puffy went on to found not only a record label but a full-service fashion and media division, culminating with his launch of Revolt TV just this year. Jay Z co-founded his own label, then ran Def Jam for a few years of his "retirement" before splintering off to manage artists as well as athletes via his very own Roc Nation. 

While Jay and Puff have dominated conference rooms within entertainment culture and fashion, 50 Cent proved his business savvy outside the box, with his most notorious windfall having come in exchange for his early endorsement stake in Glacéau, which was sold to Coca-Cola in 2007 for $4.1 billion in cash. "I took quarter water sold it in bottles for 2 bucks;/Coca-Cola came and bought it for billions, that's what's up." 50 walked away from the deal more than $100 million richer. Mission: accomplished.

Much like Iovine, mogul executives across the board have vastly expanded hip hop's commercial horizons. Steve Stoute left the record industry in 2004 to do advertising and brand consulting for Fortune 500 brands. In a 2010 write-up of 50 Cent's unprecedented payday, the Washington Post chronicled the late Chris Lighty's capitalization of the Violator brand to sell more than just CDs, concert tickets, and sneakers:

At his Violator management company (named after a rough crew that Lighty ran with as a kid), Lighty helped pioneer the use of 900 numbers for his artists. Over a decade later, he negotiated a different kind of phone deal: 50 Cent cellular ringtones to be sold for up to $2.99 per download. Lighty inked other agreements, too: a video game and a biopic with MTV Films and Paramount Pictures.

By 2003, the entrepreneurial spirit that launched FUBU in 1992, Sean John in 1998, and then Rocawear in 1999 had expanded beyond fashion to multimedia, minting a few multimillionaires along the way.

The d-boys are posted and in vogue as ever, but hustle is redefined. The past couple decades of hip hop—driven, in fact, by Bad Boy, Interscope, and R.O.C. headliners—have promoted multimedia and industrial conquest as rap's highest aspiration. Last year, not long after the launch of just her second album, Nicki Minaj was financing upstart moscato brands and hitching her star to American Idol. Even Meek Mill, a street rapper by all measures, stresses in interviews that goon life is a dead end, hence his grinding behind a studio mic since his braided teen years to perfect his craft and achieve national fame, rather than loiter as just another locally notorious dope boy.

Rappers brag or die by their "credibility," however that signifies their fanbases these days. In 1988, it was inconceivable that Dr. Dre would break a Forbes wealth record as the head of a best-selling audio brand and adviser to the most valuable tech company in the world. Not that Puff or Jay are too far behind him. For now, though, it's Dre Day, and everybody's celebrating.

Justin Charity is a fiction writer and freelance struggle correspondent. He tweets as @BrotherNumpsa.

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