Manchester United fans are confident the decision of the Old Trafford board to end talks with Malcolm Glazer will end the US tycoon's takeover attempt.
United said the offer "was not in the best interests of the company" as it relied too much on borrowed money.
Mark Longden of the Independent Manchester United Supporters' Association told BBC Sport: "There's no way the guy is going to come back.
"We would now like to see him sell his shares back to ordinary supporters."
Longden said the United board's announcement made a hostile takeover Glazer's only realistic option if he wanted to pursue his interest in the club.
"We knew he never had the money and the board admitted he did not have the money. That is a powerful argument for us," he added.
"A hostile bid will cost him a damn sight more."
IMUSA's view was shared by Shareholders United, which has also fought against the club being bought by Glazer.
"This looks like the final nail in Malcolm Glazer's coffin because JP Morgan [Glazer's bankers] do not back hostile takeovers," said SU spokesman Oliver Houston.
"It is fantastic news and due in no small part to the campaign we have waged against him.
"The fans have led from the front and I hope the board will recognise that and give them some kind of payback.
"We have rallied to the cause to protect our club and we would like a meeting with the board ahead of the AGM on 12 November to discuss how we can go forward together.
"It's time for the board, the manager, the players and the fans all to be working in the same direction."
Longden added that IMUSA and Shareholders United had been in contact with the club on Monday to request a meeting with chief executive David Gill.
"We need to try and find a way with the board to make sure this does not happen again," said Longden.
"There must be imaginative ways in which the board can put more shares in the hands of the supporters.
"We don't want a Roman Abramovich-style person taking over our club without the backing of the fans."