Pinsent Curtis is claiming that it has completed the first ever shipping deal under the private finance initiative (PFI).
The Natural Environment Research Council instructed Pinsent Curtis on the financing of its #30m ship, Polar Queen.
The vessel, which is being leased from a Norwegian shipping company advised by Richards Butler, will be renamed Ernest Shackleton.
The British Antarctic Survey (BAS) will use Ernest Shackleton to replenish its research stations in the south Atlantic and Antarctica.
Michael Boyd led the Pinsent Curtis team, which worked closely with the Natural Environment Research Council's in-house team.
Boyd, who completed a #117m hospital PFI in March, says: "There was no precedent to follow and we had to prepare documentation that would ensure a successful marriage between the requirements of PFI and the dynamic area of shipping law.
"The closure of this deal means that Pinsent Curtis has now seen six PFI transactions worth a total of nearly #270m complete this year."
Pinsent Curtis is advising on a further 31 PFI deals.
Among other projects, it is advising the Metropolitan police on the outsourcing of its information technology, worth #425m.
The firm has also been retained by the Royal Bank of Scotland to advise on a #42m pathfinder project for new mental health facilities in Leeds.