In July last year, 31-year old Fabius bought a 280 metre square apartment that belonged to French film director Claude Zidi.
Tracfin, the French agency charged with investigating money laundering, was notified, but there was no inquiry launched, said Le Point, the magazine that broke the story.
“How was the son of the government’s second-in-charge, who pays no taxes even though he is a fiscal resident in France, able to acquire seven million euros without Bercy [France’s finance ministry] demanding to know more,” the magazine asked.
Fabius told the magazine he borrowed money from a bank, with a loan secured against his consultancy firm TF Conseils.
Other sources suggest to the magazine the money may have come from gambling wins.
In June 2011, Fabius was fined 15,000 euros for breach of trust for misappropriating 90,000 euros given to him by an investor to finance a smart-card payment system.