According to local sources, the owner of John Laing, the fund manager Henderson, is preparing to sell John Laing and has hired Greenhill to advise on a possible sale or listing. Greenhill, which was appointed by Henderson earlier this year, also advised John Laing on the 2006 takeover.

Henderson bought the infrastructure group in 2006 for £887 million, but was subsequently sued by 22 pension funds that argued it should have invested directly in infrastructure assets instead. A High Court judge ruled in Henderson's favour in November.

The exit would be natural given that the redemption date for the Henderson's PFI fund is 2015.

The company currently owns stakes in 45 privately financed infrastructure projects.

John Laing reported pre-tax profits of £65.6 million last year and had assets under management of £1 billion. John Laing has an agreement in place to sell its infrastructure/PFI assets to the listed investment firm, John Laing Infrastructure fund.