In the first of several planned trials of foreign figures alleged to be profiting from ill-gotten gains, the defendant was absent when the trial opened on Monday and his lawyers sought an adjournment.
Lawyer Emmanuel Marsigny argued the defence needs more time to prepare, pointing out that Obiang, the son of President Teodoro Obiang Nguema and currently Equatorial Guinea's vice-president, was summoned to trial just three weeks ago.
Marsigny says there is no evidence to support the accusation of corruption - except for a statement made by one of Obiang's political opponents.
With regards to the accusation of embezzlement, he says all the transactions are clear and traceable.
And Marsigny questioned France's legal right to prosecute Obiang.
Can France apply French law to what happened in Equatorial Guinea? he asks.
"What happened in Equatorial Guinea and the way Mr Nguema earned his money is perfectly legal in his country," Marsigny told RFI.
"But we are facing one accusation that states 'We don't mind and it doesn't matter, the fact that you earn your money applying your law in EG, if you had done this in our country, in France, it would have been illegal, so the funds that you use are illegitimate and so you are guilty of laundering money.' I think that everyone could easily realise, understand that this is something that couldn't work."
To support his case, Marsigny cites a hypothetical case.
"If, for example, someone is investing money in the marijuana business in Colorado or in some states in the US where it's legal and if he invests his money in Paris, buying one apartment, well, following the reasoning made for Mr Obiang, that person will be sentenced for laundering money of drug trafficking, so it makes no sense," he argues. "What is legal in a country is legal in this country, and France cannot say that it's illegal, applying French law to situations that are not relevant to French jurisdiction."
"Bullshit" is the response of William Bourdon, a lawyer who is president of Sherpa, a Paris-based group set up to defend victims of economic crimes that is one of the plaintiffs against Obiang.
"They forget - because they speculate on the amnesia of public opinion and sometimes journalists - they have attempted to obtain from the judge, from the court, from the supreme court, decisions by which it could have been stated that there was no jurisdiction, that he could be the beneficiary of impunity, and all the motions have been rejected, all of them!" Bourdon told RFI.
"So they continue their propaganda they hope that by repeating again and again lies, and the bigger the lie the more efficient it is nowadays. But in the end, I'll repeat it again and again, he will be convicted."
According to Marsigny, NGOs bringing this sort of case have ulterior motives.
"In Obiang's case, if someone is a victim, for example, victim of the embezzlement of public funds, the victim is the republic," he insists. "And, talking about corruption, there's no investigation, there's only one accusation, there are no evidence. I think that by using a criminal trial these NGOs are trying in fact to destabilise and take down the chiefs of states and the people in charge of those countries."
Change in French policy
The trial marks a major shift for France, which anti-graft campaigners say has long turned a blind eye to corrupt African leaders buying Parisian real estate.
But it is also relevant on an international level.
"What's at stake personally, for the indicted, is extremely important because what he wants is to suffocate by all possible manoeuvres, as he's tried to do it ever since the beginning of these proceedings, for obvious political reasons," Bourdon says.
"He wants to replace his father, it's a kind of battle in the corridors of the presidential palace in Malabo, and Obiang belongs to these prominent international corrupters, who systematically use the same instruments to victimise themselves, to descredit the tribunal, to spit on the civl parts and the victims."
Bourdon draws a comparison with other leaders being pursued in a broader French probe known as the "ill-gotten assets" investigation.
It is looking into Gabon's leader Ali Bongo and Congo Republic leader Denis Sassou Nguesso.
"Greed is universally an endless source of ambition and energy, which can crush and squash all the democratic ambition which can be at the origin of main violation of human rights," he comments. "Look what's going on in Brazzaville, Sassou Nguesso imposed a new mandate against the will of his own people, because he knows that, if he quits power ... he will be accountable for all the bribes, all the embezzled money he organised for many years for him and his clan and family."
Bourdon says this trial opens a new door, it gives hope to people living in countries that suffer from high levels of corruption.
More importantly, he says, it might help put an end to impunity for corrupt heads of state and their families.