Italy's highest court ordered a re-trial of former top executives at defence group Leonardo Finmeccanica (LDOF.MI) over allegations of bribery in a 2010 contract to provide a dozen helicopters to the Indian government.
In April a Milan appeals court sentenced former Finmeccanica CEO Giuseppe Orsi to four and a half years in prison for corruption and falsifying invoices, overturning a previous lower court ruling.
Bruno Spagnolini, former head of the group's helicopter unit AgustaWestland, was sentenced to four years in jail over the 560 million euro ($585 million) contract.
The case went to the highest court after the two executives launched an appeal.
Both executives will now have to be tried again in front of Milan's appeals court.
Last week India's federal police arrested the former head of the air force S.P. Tyagi, 71, who was at the centre of allegations of impropriety in the order of 12 helicopters meant to fly senior Indian politicians.
The deal was cancelled in 2014 after Orsi was arrested on suspicion of paying bribes to secure the deal.
AgustaWestland opposed India's decision to cancel the order and the contract is currently suspended and the subject of international arbitration in Paris.
The case against Finmeccanica itself was dropped by prosecutors back in 2014 while AgustaWestland agreed on a 7.5 million-euro settlement with the court the same year