Commenting on his resignation, Lee (pictured) revealed he already had a job opportunity in place, which could only be disclosed after he ceased to be an OMG employee.
Doug Pearce, CEO of Omnicom Media Group China, said Ian has been a "highly-valued contributor" in establishing the agency's finance and operating platforms and building up a "very solid" in-house digital trading team.
Over the past seven years, Lee rose through the ranks from finance director to CFO, before being promoted to his current role in September last year. Prior to OMG, he held senior positions at STAR TV and ChinaByte.com.
OMG has recently boosted its management team with the internal appointments of Arlene Ang as CEO of Omnicom Media Group, Digital; Gloria Li as CEO of Opera, OMG's buying unit; and Mentor Zhu as managing director in Bejing.