Simon Parker, the managing director, John Hounsell, the financial director, and the client services director, Peter Smith, now own 100 per cent of the agency.
Hounsell and Smith have been with TCS for more than 20 years, while Parker joined the company in 2006 from Golley Slater.
TCS, with offices in London, Manchester and Worcester, had billings of £14.8 million in 2006, according to Nielsen Media Research figures.
Parker said: "Our objective is simple: to stay completely independent, offering clients great media planning and buying, underpinned by exemplary service levels."
TCS Media, which has a client list that includes Laura Ashley, Olympus and Fulham Football Club, was founded in 1977 by Clemens, Milan Simek and Keith Tuckey.