Kroenke accepted an offer to be a non-executive director at Arsenal in 2008
American tycoon Stan Kroenke has increased his stake in Arsenal to just over 20%, at a cost of £42.5m.
He has purchased 5,000 ordinary shares at £8,500 apiece from fellow Gunners director Danny Fiszman.
Previously, Kroenke had held a 12% stake in the club largely as a result of shares his firm Kroenke Sports Enterprises purchased from ITV in 2007.
In September 2008, Kroenke accepted an offer to become a non-executive director of the Premier League club.
"After having been invited to join the board last year I am delighted to be able to increase my shareholding in Arsenal," said Kroenke.
"I will continue to work closely with my board colleagues to maintain the stable environment in which the club operates and to preserve the self-sustaining business model enjoyed by the club."
If KSE - which also owns the Denver Nuggets basketball franchise, the Colorado Avalanche ice hockey team and Major League Soccer side Colorado Rapids - increases its stake to 30% it will be obliged to launch a takeover bid under financial regulations.
However, the Arsenal directors have a "lockdown" agreement in place - which means they cannot sell their shares to anyone before April 2009 other than a limited number of people, such as family members.
After that, until October 2012, they cannot sell to anyone else without giving the other directors the first option to buy.
Kroenke is now the second biggest shareholder in the club behind Uzbekistani metals magnate Alisher Usmanov, whose Red and White Holdings group owns 25% after paying about £75m for the 14.65% holding previously held by former vice-chairman David Dein.
Lady Nina Bracewell-Smith left the Arsenal board in December - thus freeing her from the directors' agreement - and could be willing to listen to offers for her 15.9% holding.
Fiszman, whose stake now stands at 16.1%, declared himself pleased with Kroenke's commitment to Arsenal but revealed he would not be selling any more of his shares in the club.
"I am pleased that Stan Kroenke has made a further substantial commitment to the club by acquiring approximately a third of my holding," stated Fiszman.
"I will of course continue to work for Arsenal with the best interests of the club at heart and have no intention of selling any more of my shareholding."
The Arsenal Supporters Trust (AST) holds 3% of shares through its members, but represent a collective of small shareholders who have about 12%.
In a statement, it said: "The fact that Stan Kroenke is already a member of the board at Arsenal should ensure that this change does not create any instability.
"We were supportive of him joining the board and welcome the sporting and commercial expertise he brings to the club.
"If a sale had to take place, we are reassured that it is to Stan."
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