For rap’s underrated cult heroes, regional stars, and former hitmakers, you'd imagine that there’s no greater vindication than getting props from a current superstar—whether explicitly or implicitly. Apparently, though, for Rappin’ 4-Tay, hearing several lines from his 1994 classic "Playaz Club" spit by Drake, only slightly reworded and delivered with essentially the same flow, on YG’s new single "Who Do You Love," was not a wholly flattering experience. A few days after the song leaked, Rappin’ 4-Tay tweeted “In This Song Drake Copys My Lyrics & Lines From My PlayazClub Song & Pays No Homage!???” Drake may have intended the very obvious mimicry as homage, but 4-Tay thinks that something more, perhaps a shoutout by name, would’ve made it more of a tribute than a jack move.

Similarly, the Chicago group HotStylz wasn’t as thrilled as you might expect when their sole hit, 2008’s "Lookin’ Boy," became the basis of an extended riff in Eminem’s recent song "Rap God." It may have been the first time most rap fans had given HotStylz a second thought in years, but the group was incensed enough to retaliate with "Rap Fraud," jacking flows and beats from several Em songs and taunting him on sensitive subjects like his daughter Hailie. HotStylz member Raydio G explained in a Yahoo! Music interview that the lack of a reference to the group by name, or a writing credit for the interpolation contained in Eminem’s song, made it feel “more like theft than paying homage."

Nobody believes that Eminem or Drake needs to steal anybody else’s ideas to make a hit.

Nobody believes that Eminem or Drake needs to steal anybody else’s ideas to make a hit. But is there an etiquette they violated with those songs, or are the lesser known artists they quoted simply hungry for publicity? A few hours of “Hey, did you catch that reference?” Twitter buzz may look to them like an opportunity to extend their time in the spotlight with a few days of controversy. Drake has always been eager to show off his rap-nerd creds—a couple years ago, he borrowed a couple lines from another West coast rap legend, the late Mac Dre, on the megahit "The Motto." Of course, that situation was different, both in that Drizzy mentioned Mac Dre by name, and in that Dre wasn’t around to voice an opinion, good or bad.

But Drake’s ear for mimicry has long been a defining trait. While he’s emerged from early comparisons to his mentors Lil Wayne and Kanye West to be respected as an artist with his own distinctive sound, he continues to be a sponge for other rappers’ styles. Most notably, this summer, he appeared on the hit remix to "Versace" by Migos, adopting the Atlanta trio’s distinctive triplet rhythms with the group’s approval. Since then, he’s continued to ape the Migos flow on more recent tracks like "The Language" and "We Made It (Remix)." Even borrowing flows from his pal Lil Wayne has landed Drake in murky legal territory. His breakthrough hit "Best I Ever Had" used a flow from Wayne’s "Do It For The Boy," which gave that track’s producer, Kia Shine, a basis to claim a writing credit, even though Drake had only interpolated Weezy’s vocals, not Kia Shine’s beat.

Drake is only one of several artists who’ve recently acknowledged Ma$e’s enduring influence, spitting "Mo’ Money Mo’ Problems" bars on "Worst Behavior." Pusha T’s "Let Me Love You" and Rico Love’s radio hit "They Don’t Know" feature outright impersonations of the shiny-suit era Bad Boy star. Juvenile, who like Ma$e was once a major star and now exists on the periphery of mainstream rap, has also enjoyed something of a resurgence as an influence, with "Used 2" by 2 Chainz and "Part II (On The Run)" by Jay-Z both featuring the flow from Juvie’s "Back That Azz Up." These all seem like friendly homages among peers and acquaintances. However, “Used 2” was produced by Mannie Fresh and featured Juvenile and some of his Hot Boyz groupmates in the New Orleans-based video, making the whole thing essentially a tribute to vintage Cash Money.

That so many songs are being built around borrowed flows, and that the practice has become a flashpoint of discussion, suggests that fans have a more sophisticated view of flow than they may have in the past. Too often, rapping gets boiled down to lyrics—verses that exist as a text for the close-listening connoisseurs, while the hooks and beats pull in more casual listeners. But the cadence and meter of a verse, the way syllables are clustered together and spaced out, the way certain vowel sounds are slurred or elongated, all these things contribute to the musicality of a rapper’s performance, and hugely impact the listening experience. That the "Versace" flow is widely recognized as catchy in and of itself—not just the part where the word "Versace" is repeated over and over, but the verses—is, in a weird way, a sign of the times.

One artist who recognizes the importance of flow better than most is Future. When he felt his style was being too widely imitated, he came up with something forcefully, almost awkwardly different for last year's “Karate Chop.” When that got played out, he came up with an even more distinctive, halting flow on “Sh!t.” Now a new artist, Que, is blowing up with a song, “OG Bobby Johnson,” that apes “Sh!t” virtually syllable for syllable. Surely Future will debut yet another new style soon enough. “Every record I do, I try to reinvent myself," he told The Fader in November. “A different day calls for a different style. I record between three to seven songs in a night, and I don’t do the same style over every beat.”

Is the Migos flow just a slight spin on the triplet-heavy style that’s been practiced by Big Sean and Kendrick Lamar in recent years?

Of course, when there aren’t words being quoted or clear homage being paid, there will always be some argument as to who originated a flow. Did Future cop the "Karate Chop" flow from Travis Porter’s "Make It Rain" or Lil Reese’s "Us" or Soulja Boy’s "Gucci Bandana?" Is the Migos flow just a slight spin on the triplet-heavy style that Big Sean and Kendrick Lamar have been employing in recent years, or do Bone Thugs-N-Harmony and Three 6 Mafia deserve the credit for pioneering that delivery style in the '90s? Am I the only person who thinks that Kanye West jacked both the flow and the minimal percussion of "New Slaves" from Meek Mill’s "Dreams & Nightmares?"

When flows are mimicked and borrowed, does the relative obscurity of the source material matter? Jay-Z famously defended his right to quote his old friend Biggie Smalls on 2003’s "What More Can I Say," and certainly nobody can accuse Jay of trying to trick anyone into thinking he wrote a line that first appeared on the millions-selling Life After Death. But the boast of “I’m a writer not a biter” was soon used against him in a sound collage of the many instances in which he’d quotes another MC’s words and flows (an mp3 that circulated for over a year before Cam’ron appropriated it for his beef with Jay in 2006). Is it Jay’s fault that "99 Problems" is so much more famous than the songs it liberally borrows from, or is it just too bad that all Black Album-era Jay-Z fans haven’t studied up on Ice-T or UGK?

Superstars like Drake or Jay-Z are damned if they do and damned if they don’t. Whatever acknowledgment they show to other artists will be deemed insufficient by someone, often the artists themselves. But should they be obligated to wipe their music free of obvious influences, to not borrow and reference the way virtually all rappers do on a routine basis? Does any flow need to be cleared and co-signed like a sample? Would A$AP Ferg have been called out for biting one of his ‘90s heroes if he hadn’t loaded up Trap Lord with cameos from members of Bone Thugs, Onyx, and Cypress Hill? The chatter over Drake and Migos has proven that actual collaborations don’t inoculate an artist against charges of theft. But as Internet rap fans become more and more attentive to every detail of every new song, artists should be aware that whatever influence they draw from someone else’s song is going to get a reaction, perhaps even a salty word from the artist whose work inspired them.

Al Shipley is a writer, not an aggregator. You can follow him at @AlShipley.

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