David Ross has made an approach to take Cosalt, the offshore safety company he chairs, private for 0.1p a share, or £400,000.
The co-founder of Carphone Warehouse, whose father and grandfather also chaired Cosalt, already owns 15 per cent of the company, which had a market value of £3.2m on Wednesday. Its shares slumped 38 per cent to a new low of 0.475p yesterday and the company warned that it is likely to use up its borrowing facilities before the end of the year.
"This company clearly needs more money – it has only just had a fund raising [through the £27m sale of its marine business] and that clearly wasn't enough," Roger Hardman, an analyst at Hardman & Co, said.
He added that Cosalt is being held back by a lack of capital. The company's net debt is £12.3m, an amount that includes more than £3m in loans from shareholders including Mr Ross.
Cosalt was founded in 1873 as a co-operative of boat owners, including Mr Ross's great-grandfather, as the Great Grimbsy Coal, Salt and Tanning Company.
Mr Ross's grandfather bought out the company, which was floated on the Stock Exchange in 1971.