The American business tycoon had given investors until 3pm yesterday to offer to sell their stake in the Old Trafford club.
Although Glazer will not formally confirm the exact shareholding until early this morning, it is believed he has acquired the 0.3% he needed to purchase the remainder of the club.
Glazer had set a second deadline after only accruing 97.3% of shares when the original timescale came to an end a fortnight ago.
But now he has bridged the gap, any shareholders who have not sold will be forced to do so within the next three months.
It will quash any internal attempt to quell his power even though major fans groups Shareholders United and the Independent Manchester United Supporters' Association have vowed to continue the struggle to oust him.
The announcement is largely academic given Glazer is already in control of the Red Devils and has nominated sons Joel, Avi and Bryan to the Old Trafford board.