Russian businessman Alisher Usmanov has increased his shareholding in Arsenal to 21%.
The purchase means Usmanov's company is now the second-largest shareholder after Danny Fiszman, who has 24%.
He fight bought into Arsenal after paying former vice-chairman David Dein around €75m for his 14.65% holding last month.
Usmanov's move, announced to the Stock Exchange this morning and comes after a £2.6m investment in Arsenal shares yesterday.
Usmanov is now the club's second-highest shareholder behind Danny Fiszman, on 24%.
The club release their financial results on Monday. The move to the Emirates Stadium is expected to have helped them close the gap between themselves and Chelsea and Manchester United.