When Drake's highly-anticipated sixth studio album Certified Lover Boy arrived Sept. 3, it came with a laundry list of features, interpolations and samples in its credits. Those included longtime collaborators like producer and engineer Noah "40" Shebib and OVO signee PARTYNEXTDOOR, as well as reappearances by old friends like former Young Money labelmates Lil Wayne and Nicki Minaj.

But the album also included some more surprising guests. Due to a sample of Masego's "Navajo" on the album opener "Champagne Poetry," Drake shares writing and production credit with The BeatlesJohn Lennon and Paul McCartney. ("Navajo" samples a cover of the Beatles song "Michelle.") Right Said Fred is on there too, with the band's iconic "I'm Too Sexy" sampled and flipped into the album's Billboard Hot 100-topping, cheeky focus track "Way 2 Sexy," as well were *NSYNC and R. Kelly, who are both sampled in the song "TSU." (Shebib clarified in an Instagram post that R. Kelly is not a lyricist on "TSU" but that they "were forced to license" his song "Half on a Baby" in order to use a clip of OG Ron C talking as a sample in which an R. Kelly song plays faintly in the background.)

But even after Drake's album was released, a source close to the situation told Billboard the writing credit splits -- meaning which collaborators get what share of a song -- are not yet finalized. In fact, releasing songs and projects prior to determining official splits for each songwriter is normal in the music business, especially for albums with significant money to be made and many writers' interests to reconcile.

"Late splits after release are commonplace," says Kelley Fox, head of publishing and records at Unknown Music, an independent label and publishing company founded by songwriter Ross Golan. The process can be complicated, and it can get especially hairy for sample-heavy genres like hip-hop, due to the complex nature of determining percentages of ownership between writers in the room and sampled or interpolated writers who were not present.

"At the end of the day, creatives have different ideas of what they contributed in the room," says Fox. "There is no rule that says that because you came up with the concept, you definitely deserve 5%. That's really why it's so hard to figure out."

Additionally, songs are often written months or even years before they are released, so when writers have to argue for their piece of the publishing royalty pie after the release of a song, they are often working off of old, uncertain memories of the session. And greener songwriters are left to fight for their fair share with their more seasoned, well-known counterparts.

The stakes for these negotiations are high, especially when the song is attached to a hit-making artist like Drake. This week, songs from the Certified Lover Boy make up nine of the top 10 slots on the Hot 100, while all of the album's 21 tracks are in the top 40 of the chart, as it racked up 743.67 million on-demand streams, second all-time behind his 2018 album Scorpion.

And that can mean big money. For Drake's 2016 mega-hit "One Dance" feat. Wizkid and Kyla, for example, the publishing revenue accrued so far totals at least $4 million, not including synch and general licensing, i.e. royalties from when it's played in stores, elevators, or hotels, Billboard estimates. And that's just in the U.S. -- the IFPI named "One Dance" the biggest song in the world in 2016. In that case, the difference between securing 15% songwriting credit and 25% on a song -- even one with nine credited writers -- can be, as Fox puts it, "As big as you buying a house or not buying a house."

Additional reporting by Ed Christman.

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