The Glazer family will part with about five per cent of United's shares on the New York Stock Exchange, which is set to earn the American investors US$154.5 million (£91.4m).
The current share price on the NYSE for United is $19.31, after Wednesday's trading.
A press release stated the Premier League powerhouse would not be beneficiaries of the share sale, only the owners.
"Manchester United will not receive any proceeds from the sale of any Class A Shares by the Selling Shareholder," the statement read.
"The Class A Ordinary Shares are listed on the New York Stock Exchange under the symbol 'MANU.'"
The Glazers appear to be cashing in on the club's renewed optimism, after replacing David Moyes with Louis van Gaal as manager.
When Moyes' sacking was confirmed, United's share price had dipped to US$14.98, but had already bounced back to $16.74 by the time Van Gaal was appointed.
