Amateur video of the Buncefield fire in December 2005
The High Court has ruled that oil company Total is liable for damages caused by the explosion at the Buncefield oil depot in Hertfordshire.
The Hemel Hempstead site was the scene of an explosion which injured 40 people and left homes and businesses damaged.
The blast in 2005 was the largest in Europe since the end of World War II.
The depot was operated by Total, which owned it in a joint venture with Chevron, called Hertfordshire Oil Storage Ltd (HOSL).
The ignition of the vapour cloud which followed the spillage of 300 tons of petrol, caused an explosion which caused a tremor equivalent to a 2.4 magnitude earthquake.
The High Court hearing was over a dispute between Total and Chevron as to who was liable for the agreed acts of negligence that led to the spillage and explosion.
Chevron claimed Total was to blame, while Total said the joint venture company HOSL should bear responsibility.
The court said Total had failed to discharge the burden of establishing that HOSL was responsible for the negligence of the supervisor.
It found that all those working at the site had contracts with Total; the terminal manager who was the most senior member of staff on site was appointed by Total and line managed by Total.
All safety instructions were developed by Total.
The court also found there was a further contributory fault due to the failure by Total's head office staff to develop an adequate system for preventing the overfilling of a tank.
It also said Total was not entitled to recover a contractual indemnity from HOSL or Chevron in respect of all or any part of the claim.
Chevron said it was "happy" with the judgement, while Total said it was considering an appeal.
In a statement Total said: "We still believe... our joint venture partner should accept their share of the responsibilities for the incident.
"As a consequence we will be considering our grounds for appeal."
It added: "We would like to stress that any appeal will have no implications for claimants, whose claims will continue to be processed."