FORMER French president Nicolas Sarkozy was named a key witness after 12 hours before a judge to answer questions about whether he accepted illegal campaign donations from 90-year-old L'Oreal heiress Liliane Bettencourt.
Ms Bettencourt's former accountant told police she handed over €150,000 in cash she was told would be passed on to Sarkozy's campaign.
The sum shocked many French citizens because spending on political campaigns is tightly controlled.
The investigation that has ensnared Sarkozy centres on the finances of Ms Bettencourt, Europe's richest woman.
Ms Bettencourt, who was reported to suffer from Alzheimer's, has since been placed under legal protection.
Sarkozy's election loss in May cost him his immunity from prosecution. By July, his offices had been raided.
Investigating judges, who met Sarkozy and his lawyer privately, stopped short of filing preliminary charges, as some had expected.
Sarkozy's status is somewhere between a simple witness and a formal suspect.
Sarkozy ally Patrick Balkany, a deputy and mayor, said the ex-president "was content".
Ms Bettencourt's money was contested long before Sarkozy entered the picture.
Her daughter accused a celebrity photographer of abusing her mother's alleged mental frailty and conning the elderly heiress out of €1bn.
Liliane Bettencourt's ex- butler leaked details of household conversations, including one in which the mother seems confused about whether she gave an island in the Seychelles to the photographer.
The island has since been sold to a wildlife organisation.