The majority of the redundancies are from the agency's creative services and planning sectors; none have been made in the agency's PR business.
Mather was brought in from ad agency BBH in October to integrate Exposure's UK business. Exposure and Mather told PRWeek that this strategy was not working.
Mather left Exposure at the end of April and is understood to have returned to BBH.
Exposure has now decided not to integrate its UK business and will return to operating as four autonomous business remits: PR, brand experience, digital and social, and fashion.
Rather than replacing Mather, heads of the four departments have been put in place.
Exposure founders Raoul Shah and Tim Bourne remain joint CEOs of the global group, which operates in London, New York and Tokyo with a team of 200 PR professionals, and climbed to 20th position in this year's PRWeek Top 150 agency rankings.
Exposure makes redundancies following exit of UK managing director
Exposure has made nine redundancies in London following the resignation of UK managing director Keir Mather after just seven months in the role.
