After the move was reported earlier today, the board of Trinity Mirror has now finalised Fox's appointment as the successor to Sly Bailey, who left the firm in June. He will start in the role on September 10.
The 51-year-old was hired followed an "extensive search" in conjunction with headhunters Egon Zehnder, in which a wide field of external and internal candidates were apparently considered.
Trinity Mirror said that Fox has led 90-year-old retailer HMV through a "turbulent period" over his six years in charge, and "played an invaluable part in securing a profitable future" for the firm as it copes with online competition.
Despite overseeing various store closures and seeing sales fall below £1 billion for the first time since HMV floated, Fox leaves the retailer with it forecast to make a £10m pre-tax profit in 2012/13.
Trinity Mirror has selected him to lead its business primarily as he "understands structurally changing sectors".
David Grigson, the Trinity Mirror chairman, said that Fox will provide "strategic leadership" for the company as it attempts to cope with the ever increasing proportion of people getting their news online.
"His experience gives him a current and in-depth understanding of how consumers' habits are changing and the technology that is driving these changes," said Grigson, who is also chairman of Anobii, the digital books venture in which HMV recently sold a major stake to Sainsbury's.
"He is a great team player and leader and his skills and experience perfectly complement those of the existing executive team."
Fox will be paid an annual base salary of £500,000 at Trinity Mirror and a bonus potential of 75% of his salary, of which half is payable in cash and the other half in restricted shares deferred for three years.
For 2012, the bonus will be "subject to a series of stretching operating profit and revenue targets", said Trinity Mirror.
He will also receive a one-off joining grant of performance shares equivalent in value to 120% of his salary, but vesting of these shares will be dependent on more performance and growth targets.
"I am delighted to be joining the Trinity Mirror team. I have been enormously impressed by the people I have met so far and look forward to starting shortly," said Fox.
"Whilst the Group's current financial performance is robust, we will need to continue to evolve the business to meet the changing needs of our customers."
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