So they've changed the lox.

Russ Cowan confirms that he has sold the Rittenhouse Square offshoot of his Famous 4th Street Deli to Brooklyn-bred Rich Kaufman and partner Ken Keating, who have renamed it Kaufman's.

The change, noted this morning by Foobooz.com, was quick, Cowan told me.

"The whole deal came together in about three weeks," he said.

Cowan opened the deli-restaurant, at 38 S. 19th St., in 2009 as an adjunct of the Famous flagship at Fourth and Bainbridge Streets, which he bought nearly 10 years ago. That location is unaffected.

Cowan, who has opened and sold 19 delis over the years, said he owned the shop "much longer than I thought I would."

Both Kaufman and Keating, who worked in delis years ago, recently left jobs with the mortgage department at Wells Fargo. "This is a life-changing moment," Kaufman told me.

They expect to keep everything as-is, including staff.

His name hangs over the door. "We were joking, if we were opening an Irish pub, then we'd use his," Kaufman said.