The two men are said to be clashing over their respective valuations of the club, despite ongoing talks for two months, with Trew understood to be wanting between £8m and £10m for Notts.
By allegedly signing the agreement, it would suggest that Hardy, who owns The Nottinghamshire Golf, Hotel & Country Club and is chief executive of Nottingham-based group Paragon, is a serious bidder.
Under the terms of the agreement, neither individual can speak publicly about any talks between them, but should they eventually agree on a price, Trew can open the club's books to Hardy for him to carry out confidential due diligence with a view to completing a takeover.
Magpies chief executive Julian Winter, meanwhile, said he had not met or spoken to Notts fan Hardy – it is understood the bidder has dealt directly with Trew from the start and will continue to do so going forward.
Winter also suggested the process may be lengthy. He told local media: "I have been involved in these things and I have never seen a quick one. Don't get me wrong they do happen from time to time, but they are not the norm."
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