A court in Switzerland on Monday said that Geneva prosecutors can share with Italy material that could shed light on the Malabu scandal.
The materials, contained in a suitcase linked to Emeka Obi, a middleman in the controversial Malabu scandal, were seized more than three years ago. Prosecutors said that it could also help in the corruption case involving oil majors Eni (ENI.MI) and Royal Dutch Shell (RDSa.L) and corrupt payments in Nigeria.
Reuters reports that in a ruling on Monday, the Federal Tribunal rejected Mr Obi's appeal to prevent photocopies of items and computer files from the confiscated suitcase from being sent to Italian prosecutors.
Last year, Mr Obi and his accomplice in Italy were sentenced to four years each for their roles in the controversial Malabu oil deal. Together with Gianluca Di Nardo, an Italian, he stood as a middleman in connecting the parties and the transfer of the funds through international bank accounts.
The Swiss court said on Monday that the case did not fall within the narrow scope of permissible appeals to the tribunal. Geneva prosecutors have been reviewing material in the suitcase to decide what can be shared with Italian authorities.
The Malabu scandal involved the transfer of about $1.1 billion by Shell and ENI through the Nigerian government to accounts controlled by a former Nigerian petroleum minister, Dan Etete.
From accounts controlled by Mr Etete, about half the money ($520 million) went to accounts of companies controlled by Aliyu Abubakar, popularly known in Nigeria as the owner of AA oil.
Anti-corruption investigators and activists suspect he fronted for top officials of the Jonathan administration as well of officials of Shell and ENI.
The transaction was authorised in 2011 by Mr Jonathan through some of his cabinet ministers and the money was payment for OPL 245, one of Nigeria's richest oil blocks.
Although Shell and ENI initially claimed they did not know the money would end up with Mr Etete and his cronies, evidence has shown that claim to be false. Shell, Eni, Mr Etete, Mr Aliyu and several officials of the oil firms are being prosecuted in Italy for their roles in the scandal.
Last September, both Messrs Obi and Di Nardo were found guilty and sentenced to four years each and had another £100 pounds confiscated in connection with the case.
The pair had opted for a quick trial for their roles in the deal. The process in Italian law offers a possible reduction in any sentence.
Before their conviction, some documents had been seized in a raid on a Swiss financier's apartment that could be crucial to the case. The raid, according to Independent newspaper, uncovered the briefcase belonging to Mr Obi.
According to Swiss prosecutors, the suitcase contained a laptop, two Nigerian passports, five sim cards and a hard drive containing 41,000 documents that prosecutors believe could be crucial to the trial.
Last year, the Federal Tribunal ruled on an appeal by Mr Obi to prevent his suitcase from being unsealed. In the ruling, the court said the confiscated material could have "potential pertinence" in the criminal investigation and the sealing could be lifted without violating Swiss law.
Its confiscation led Geneva prosecutors to open a criminal case for suspected corruption of foreign officials and money-laundering. Days later Italian authorities requested judicial assistance, arguing that the suitcase and its contents had been deliberately stashed in Geneva.
The busted Geneva apartment belonged to Olivier Couriol, a former Credit Suisse banker who has been named in two other international corruption cases. Mr Couriol, who is under investigation for his role in separate crime-related deals, said that Mr Obi was merely a friend who left the bag at his flat by mistake while on holiday.
Earlier in June, a court in Geneva said some of the documents found in Mr Couriol's possession could be unsealed and be sent to Milan but Mr Obi launched another appeal, meaning a Swiss federal court must decide on the matter.
No charges have been brought against former President Goodluck Jonathan who authorised the controversial settlement agreement and transfer of the funds to Malabu.
But that administration's Attorney-General and Minister of Justice, Mohammed Adoke, who alongside then Petroleum Minister, Diezani Alison-Madueke, signed the settlement agreement on behalf of the government, is being prosecuted in Nigeria. He is currently on exile and has never personally attended his trial.
In a new book titled "Burden of Service", the former attorney general claimed that he was being investigated for the OPL 245 scandal because Vice President Yemi Osinbajo ordered anti-graft agencies to prosecute him.
The EFCC has, however, dismissed the claim.