Before the share sale, he owned a 62 per cent stake in Sports Direct, with the 25 million shares equivalent to about seven per cent of his holding.
The move comes after Mr Ashley bought an 11 per cent stake in department store House of Fraser, acquiring the shares from entrepreneur Sir Tom Hunter.
Mr Ashley is understood to have tried to muscle in on a Chinese takeover of 165-year-old House of Fraser by conglomerate Sanpower.
The coup failed but means Sanpower, which has agreed terms on a deal valuing the chain at more than £450m, is denied full ownership and is taking 89 per cent of the business.
Mr Ashley is understood to have long held ambitions to buy House of Fraser, which has branches in Darlington, Gateshead and Middlesbrough, to use it to sell Sports Direct brands.
However, it is believed investors raised doubts over a low ball offer from Mr Ashley and rejected the idea of his involvement to focus on operating as an upmarket department store.
Sports Direct is known for its budget sportswear brands, including football shirts and boots.
Mr Ashley does not take a salary as its executive deputy chairman and received a setback last week when plans to play him a shares windfall of worth more than £70m were scrapped after investors failed to back the award.
The sale of 89 per cent of House of Fraser to Sanpower, which has more than 100 businesses in mainland China, puts paid to separate plans that were being considered to float the chain on the London Stock Exchange this summer.
The department store, which generates sales of £1.2bn a year and employs 7,300 people, has held a protracted search for new investors in the last year.
The chain's origins lie in a small drapery store in Glasgow and it first listed on the stock market in 1948, remaining a public company until it was bought by Mohamed al-Fayed in 1985.
It was listed again in 1994 before being snapped up in 2006 by a group of investors led by Icelandic tycoon Jon Asgeir Johannesson's Baugur Group in a £350m deal.
Sanpower is run by tycoon Yuan Yafei, whose empire spreads across finance, property, media, transport and IT and now employs 30,000 people with assets worth nearly £5bn.