Schmid came to Halpern in April after spending two years as client services director of Good Relations and five years as the comms director of TalkTalkGroup.
Schmid’s appointment to Halpern coincided with the firm's expansion into the PR and comms market in New York alongside parent company The&Partnership, which is backed by WPP.
Schmid’s goal, when he joined as managing director, was to add new accounts to industries where Halpern already had clients, as well as build the corporate PR function.
Halpern confirmed Schmid’s departure to PRWeek.
In a statement, Clare Woodford, deputy managing director of Halpern, said: "Mark is leaving Halpern to be a founder and director of ibetboxing.com... which launches at the end of October."
ibetboxing.com describes itself as 'the world's only betting website for boxing fans'. The website contains nothing other than a promise that it is "coming soon".