The Arsenal Supporters Trust has called for all shareholders to unite behind the board and welcome the investment of Stan Kroenke.
The Takeover Panel is looking into Kroenke's recent £42.5m purchase of shares from director Danny Fiszman, amid concerns from other shareholders the American billionaire may be receiving preferential treatment in the buying of stock.
Kroenke, the club's single largest stakeholder at 28.3% ahead of Uzbek billionaire Alisher Usmanov, last year accepted an invitation to join the club's board and last week his company bought 4,839 shares from members of the Carr family, including Arsenal director Richard Carr.
Should the Kroenke Sports Enterprise group holding reach the 30% threshold, under financial regulations they would be obliged to launch a formal takeover.
Arsenal, however, are adamant there has been no improper behaviour nor any rules broken.
The AST - whose members hold around 3% but act as the voice for small shareholders who together own about 12% of the shares - have long championed the involvement of Kroenke and believe everyone must pull in the same direction.
''The AST regrets that a shareholder has chosen to involve the takeover panel,'' a statement said.
''Their complaint is about protecting shareholder value. We represent Arsenal supporters who own shares as custodians of the club.
''Our primary interest as shareholders is what is good for Arsenal Football Club rather than trying to make money.
''Once again we would urge all of the major shareholders in the club to reflect that Arsenal would be much better off if everyone worked together.
''It strengthens our resolve to work to increase the number of Arsenal supporters who own shares in Arsenal.''
Gunners boss Arsene Wenger, preparing for the Champions League semi-final second leg against Manchester United, maintained the behind-the-scenes changes would have no impact on his role.
Wenger said: "There is some share movement, but no organisational or structural movement on the board.
"That does not concern too much the day-to-day work at the club."