Kanye doesn't give a flying $%&* about Jay Z's new single "Kill Jay Z," in which the 4:44 rapper claims West borrowed $20 million and goes on to address Kanye's concert rant back in November in which he slammed his mentor for not calling him after Kim was robbed at gunpoint in Paris.

We caught up with Kanye Friday at his office in Calabasas where he's probably working on some new Adidas designs and perhaps planning is own revenge single to address Jay Z's latest song.

Meanwhile, in Jay's new track, he addresses Kanye's 2004 single "College Dropout" in these lyrics: "You dropped outta school, you lost your principles / You gave him 20 million without thinkin'. He gave you 20 minutes on stage, f--k was he thinking'?"

In that 20 minutes on stage in Sacramento at the end of last year, right before Kanye suffered a nervous breakdown, West said to the crowd, "Jay Z — call me, bruh ... You still ain’t called me. Jay Z, I know you got killers. Please don’t send them at my head." He went on to say, "Beyoncé, I was hurt. I went down seven years on behalf of you. … I am putting my career, my life, my public standing at risk when I talk to y’all like this. This is a moment in the matrix, bro … Beyoncé, I was hurt because I hear that you said you wouldn’t perform unless you won Video of the Year over me and over ‘Hotline Bling.’"

It's all cool, though -- maybe -- because Kim and Kanye visited Bey and Jay at the couple's rented Bel Air mansion back in January, post Kanye breakdown. We imagine some apologies were made for the rant and all was smoothed over. But will Jay's new single reopen the wound and start a new feud? Kanye looks too happy to care! Hell, maybe he was on the phone congratulating Jay on 4:44 and on little Rumi and Sir!