The 50-year-old television personality said in a statement Thursday to People that he and Maisani remain "the best of friends" after breaking up "some time ago."
"Benjamin and I separated as boyfriends some time ago. We are still family to each other, and love each other very much," he said. "We remain the best of friends, and will continue to share much of our lives together."
Us Weekly reported Cooper and Maisani, who were first linked in 2009, attended a benefit together March 10 in New York.
The pair were spotted again at their home in Greenwich Village this week.
Cooper didn't share a reason for the split.
He told People in November that he's "definitely a workaholic."
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