An MBO bid would have to compete with interest from JCDecaux, Clear Channel and Titan.
Head of the Primesight management team is chief executive Naren Patel, who was part of the team that built up Primesight and sold it on to SMG for £35m in 1999.
His lieutenants include sales director Nigel Clarkson, operations director Paul Daniels and development director Terry Dyer.
The group has a £25m-a-year turnover and generates a profit of around £3m. Investec has valued the business at around £55m, but SMG has said it wants up to £90m for Primesight and cinema sales house Pearl & Dean, which is also up for sale.
JCDecaux Northern Europe chief executive officer Jeremy Male said he would be taking a closer look at Primesight's books. Titan Worldwide, which earlier this year bought Maiden Outdoor, is understood to have already approached SMG about the sale.
Cinema rival Carlton Screen Advertising is understood to be interested in snapping up Pearl & Dean. However, parent company ITV is itself reported to be keen to dispose of CSA.
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