The deal means that IMG, which already has the International Rugby Board and Rugby Football Union UK among its clients, will now expand its list to include the Football League, and a host of cricketing authorities comprising Cricket Australia, New Zealand Cricket, Cricket South Africa and Zimbabwe Cricket.
IMG, which is owned by by private equity firm Forstmann Little & Co, said it planned a "simple integration process" for the sports marketing company's client acquisitions, to allow them to benefit from its global distribution network.
Chris Guinness, the former president of Octagon CSI, will also be rejoining IMG. His job title is yet to be announced.
Michel Masquelier, executive vice-president and head of acquisition and sales worldwide, said: "This acquisition will enable us to remain on target to fulfil our strategic growth plans. We look forward to working with Chris and his team, who will assist us in the development of new business."
Guinness added: "The complementary nature of the two companies' businesses and the global financial and distribution strength of IMG Media make it an ideal strategic fit for CSI Sports."
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