A rep for Couric confirmed that the ABC News special correspondent and her partner have split after five years and Perlin is currently moving out of their shared New York City home.
A friend of the journalist claimed that 37-year-old Perlin and 54-year-old Couric hold no animosity towards each other and plan to remain friends.
"Brook's a nice guy, but it was inevitable because they had different priorities and perspectives, and their age difference made it a challenge, too," the source told Us Magazine.
Couric was previously married for nine years to Jay Monahan, but Monahan passed away from colon cancer in 1998.
In May, Couric stepped down as anchor of the CBS Evening News after a five-year run on the network.
She is to host the new daytime talkshow Katie on ABC beginning in September 2012.
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Watch Katie Couric close her final episode of the CBS Evening News below: