It was one of those “only-in-New York” experiences. Timothy Clark, co-chair of Covington & Burling’s private equity group, was sitting in his 42nd-floor office in the New York Times building Thursday morning when a man suddenly appeared outside his window.

The climber, Frenchman Alain Robert, was standing on a girder that marks every floor of the building, designed by Pritzker prize-winner Renzo Piano. He was “nonchalantly talking on his cell phone,” recalls Clark.