Freshfields Bruckhaus Deringer and Simpson Thacher & Bartlett have won roles on Guardian Media Group's (GMG's) sale of its 50.1% stake in Auto Trader owner Trader Media Group.

The Guardian publisher has offloaded its remaining stake, worth around £600m, to private equity firm Apax. The disposal is subject to regulatory approval and final completion.

Freshfields advised longstanding client GMG, fielding a team featuring corporate partner Simon Marchant and corporate associate Rikin Morjaria.

Simpson Thacher acted for Apax with a team led by London corporate partner Derek Baird. Allen & Overy also provided counsel to the buyout group, with structured finance partner Robin Harvey leading.

GMG chief executive Andrew Miller said: "This proposed transaction makes strategic sense as we focus GMG's activities on award-winning digital and print journalism.

"On completion, the sale proceeds will strengthen our balance sheet and position us for further investment and growth in our core business."

GMG's sole shareholder The Scott Trust has advised the board to reinvest the proceeds to the proposed transaction to safeguard the Guardian's editorial and financial independence.

The Guardian Media Group publishes theguardian.com and the Guardian and Observer newspapers.

The deal comes after Apax bought 49.9% of Trader Media Group from the Guardian Media Group back in 2007, a deal on which Freshfields also advised.

In 2008 Ashurst, Freshfields and A&O took roles on Guardian Media Group's and Apax's £1bn takeover of the business-to business arm of publishing giant Emap, with Marchant acting for Guardian Media Group on the transaction.