Meanwhile Hanover Investments, the City specialist which last week increased its share in SMG from 5.4% to 12.6% and was rumoured to be attempting to stop merger proceedings, has moved in and appointed a new management team.
Former Channel 4 commercial director Rob Woodward has been named as SMG's new chief executive, a search that had been put on hold until the outcome of the merger had been decided.
Richard Findlay, former chief executive of Scottish Radio Holdings, has been named as a non-executive chairman in place of Chris Masters who has stepped down.
Matthew Peacock, principal of Hanover Investors. has been made a non-executive director. He said the business had been "fundamentally undervalued" but that the new team would secure it an independent future.
There is now a question mark over the future of SMG's outdoor business, Primesight, and its cinema advertising company Pearl and Dean, which have been up for sale.
Hanover confirmed that the new team at SMG will now assess the situation and make a decision on what happens next.