The London-based law firm which pursued the action against oil trading giant Trafigura over the alleged dumping of toxic waste in the Ivory Coast has claimed a record £105 million in costs.
The unprecedented figure, which Leigh Day & Co confirmed was correct, dwarfed the only known comparator - the BCCI litigation, Trafigura's QC Sean Wilken told the High Court.
By contrast, he added, Trafigura's costs stood at £14 million.
Mr Wilken told Mr Justice MacDuff, who formally approved the confidential settlement of the largest ever group action last September, that if every claimant had been paid in full, that would amount to about £3 in costs for every £1 recovered.
But he said that up to Easter, cheques had been cashed by 12,250 claimants - 41% of the total - and the process had stalled since the middle of March.
He added that Leigh Day accepted that the costs were high.
Mr Wilken said: "In fact, we would say they are staggeringly high.
"I am told that this is one of the largest, if not the largest, costs claims in legal history.
"So we say this court is faced with groundbreaking claims of English lawyers in circumstances where the Ivorian claimants have not been paid in full the compensation which was supposedly the rationale of this litigation."
He added: "Bluntly, we would like to know what happened to the money we paid to settle these claims."
It was later agreed between the two sides that issues raised today should be dealt with by the senior High Court official who will assess costs at a further hearing at the end of this year.
The claims were launched against Trafigura following an August 2006 incident when thousands claimed they fell ill after "slops" were deposited near Abidjan, the African country's commercial capital, from the Probo Koala, a ship hired by Trafigura.
The oil trading firm said it regretted the incident but did not accept legal liability as the dumping was carried out by a ship contractor which acted independently of, and without any authority from, Trafigura.
When the case settled, an agreed joint statement was issued which said that more than 20 independent experts in shipping, chemistry, modelling, toxicology, tropical medicine, veterinary science and psychiatry had been appointed to consider all the issues relating to the events in Abidjan.
It read: "These independent experts are unable to identify a link between exposure to the chemicals released from the slops and deaths, miscarriages, still births, birth defects, loss of visual acuity or other serious and chronic injuries.
"Leigh Day & Co, in the light of the expert evidence, now acknowledge that the slops could at worst have caused a range of short-term low-level flu-like symptoms and anxiety."
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