Sheikh Jassim and Sir Jim Ratcliffe's Ineos Group are the main parties trying to buy the Premier League club
Reuters reported on Thursday that United were negotiating exclusivity with Qatari banker Sheikh Jassim bin Hamad Al Thani.
It follows growing speculation Sheikh Jassim's bid is likely to succeed.
However, sources have told BBC Sport exclusivity had not been granted and talks were continuing with interested parties.
At the start of this week, reports from Qatar claimed Sheikh Jassim was going to be named United's new owner, but the publication involved later issued a clarification.
However, United's share price, which had risen sharply, did not drop back fully, suggesting a belief among investors Sheikh Jassim's attempt to buy 100% of the club was going to be successful.
Earlier this month, Sheikh Jassim lodged his fifth bid for United, which remains on the table despite suggestions he would not engage with the process beyond 9 June.
Sheikh Jassim is competing with Sir Jim Ratcliffe's Ineos Group in trying to buy the Premier League club.
Ratcliffe and Ineos are willing to secure a majority stake, which would allow current owners the Glazer family to retain representation in some capacity.
The Glazers announced in November they were considering selling United as they "explore strategic alternatives".
-- Courtesy of BBC Sport