Jennifer Lopez and Benny Medina

Jennifer Lopez and Benny Medina

*Jennifer Lopez has reportedly given her manager Benny Medina a line that he must not cross when it comes to managing other people.

The line is called – “Mariah Carey.”

Page Six is reporting that Medina, who repped Carey from 2003 to 2008, wanted back in on the singer’s career, but J.Lo wouldn’t allow it.

A source told Page Six there’s a “no Mariah” clause in Lopez’s contract with Medina.

“She had it written in that he can’t manage Mariah,” said the insider.

Lopez has been with Medina since 2008. He was the one who helped expand her portfolio with the “American Idol” gig. He also orchestrated her world tour and Las Vegas residency.

Carey, who also has a Vegas residency, has gone through several managers since severing ties with Medina.

Meanwhile, an exec at the Medina Co. told Page Six, “Benny is not restricted, contractually or otherwise, from managing Mariah Carey or any other artists.” An insider in Carey’s camp said they “didn’t know anything about it,” but chuckled.