Stan Kroenke has purchased a further 160 shares in Arsenal to take his total holding of the Premier League club to 28.58 per cent.
Last year, American businessman Kroenke accepted an invitation to join the Gunners' board and he is currently the club's largest shareholder.
News of the latest purchase, which cost £1.36million, sees the Kroenke Enterprise Group edge ever closer to the 30 per cent threshold, whereby they would be obliged to make a takeover bid.
However, it has been reported Kroenke has no intentions of any such move, with chief executive Ivan Gazidis recently stating Arsenal's current capital structure is "very efficient".
This week, Arsenal's second-largest stakeholder Alisher Usmanov saw a proposal for a rights issue of new shares to generate cash for new signings rejected by the Gunners' board.