The change will be effected through an initial public offering to the London Stock Exchange at some point during the current financial year, subject to market conditions, and is part of a move by GMG to raise cash and rebalance its portfolio.
The decision means the group will be able to retain a majority stake in Trader Media Group, while simultaneously allowing further investment in its other business interests and what it describes as "the pursuit of other opportunities".
At one stage, GMG had considered a complete sell-off. In January, GMG said that it was planning to appoint an investment bank, Merrill Lynch, to review its option for selling off its non-national newspaper assets, including the Trader Media Group-published Auto Trader.
Trader Media Group, which has an annual turnover of £300m and employs more than 3,500 people across the UK and Ireland, has operations in Italy, the Netherlands and South Africa.
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