Moy has been tasked with working on strategy across the Interpublic agency’s six US offices.
He will be based in New York reporting to Nick Coronges, executive vice-president, global chief technology officer.
Moy left Isobar after 18 months in March and the agency’s parent Dentsu said he wanted to move back to the US to be closer to his family. At the time, Dentsu had indicated Moy would "help drive growth for Isobar in the US".
Before he joined Isobar as chief commerce officer in 2013, he worked for SapientNitro (now Sapient.Razorfish) for eight years.