It was believed Eminem was subbing Drake on Kamikaze because of bars like this:

"You got some views, but you're still below me
Mine are higher, so when you compare our views, you get overlooked
And I don't say the hook unless I wrote the hook
And now I'm just freestylin' in the vocal booth
And you know I've always spoke the truth
You lyin' through your teeth so much, you broke a tooth
And it ain't somethin' I need a phone to do
When I say I can't wait 'til I get ahold of you," Em raps on the title track.

And this:

"I got a couple of mansions
Still I don't have any manners
You got a couple of ghostwriters
But to these kids it don't actually matter
They're askin' me, "What the fuck happened to hip-hop?"
I said, "I don't have any answers," he rapped on "Lucky You"

But after the album dropped Em's manager Paul Rosenberg said he wasn't targetting Drake at all.

In part four of his interview with Sway, Eminem addressed all of that.

"No, here’s the thing. Drake will always be in my good graces because he did something for one of my daughters that I will never forget, and he will always be in my graces. And I like Drake. What I’m telling you with these lines is I don’t know what’s real and what’s not at this point. Because you hear shit and this rapper, that rapper. I'm telling you that I don't do it. Never have and never will. If ever need a ghostwriter I just need to put the fucking mic down. That's my personal belief. As far as anyone out here that does use ghostwriters ... That's fine."

Jump to 2:20 to hear him speak on ghostwriters and Drake.