They have been put up for sale by the club's owners.
Manchester United's owners have put £9.5 million worth of club shares up for sale.
The stock is held by Kevin and Edward Glazer and the club say they won't receive any proceeds.
It follows Avram Glazer selling 70-million pounds of shares in March of this year.

Kildare U20 Hurlers Fall to Galway in Tier 1 Clash
Leinster Championship Gets Underway with Laois Offaly Clash
Arsenal Stunned by Bournemouth as Title Race Tightens
Connacht Exit Challenge Cup After Defeat in Montpellier
McCabe Injury Fears Eased Ahead of Poland Clash
Rovers Go Top with Statement Win
Saturday Sport Update
West Ham Hammer Wolves as Spurs Drop into Relegation Zone