The resignations took place in March. Wan had been with GroupM Interaction for 15 years, while Ngan was with the agency for a decade and was a key person on the HSBC account.
Wan confirmed the news, adding that GroupM Interaction is restructuring and there is no direct replacement for their GM roles.
Meanwhile, the pair have turned their attention to the new venture. "It is the first time that we started our own business," Wan said. "The company is already up and running on a small scale of four persons."
As reported in Feburary, GroupM Hong Kong chief executive officer and media guru KK Tsang will leave the group on 31 July, after 19 years with WPP, to start his own business as an investor and mentor.
Other recent 4A veterans going independent with their own startups include: