Only one admits to being a pirate, two admit to having been aboard the elegant 88-metre three-master but only to sell goats, cigarettes and the mild narcotic khat. The other three deny ever having set foot on the boat.
The six men, aged 25 to 50, face life in prison if convicted of kidnapping and gang theft after they were arrested on land in a French airborne operation after a ransom was paid.
Le Ponant left the Seychelles on 30 March, 2008 with 30 crew and no passengers on board, headed for Yemen where it was to take on passengers for a cruise.
On entering the notorious Gulf of Aden on 4 April, the ship was boarded by pirates armed with assault rifles who forced the crew to head for Somalia.
A week later, the ship's owner, shipping giant CMA-CGM, paid a 1.7-million-euro ransom, the crew was freed and the pirates fled into the lawless sands of Somalia.
France hunted the men through Somalia, eventually intercepting a 4x4 vehicle as it left a village, finding 200,000 dollars and weapons on board.
The car's six Somali passengers were arrested and Le Ponant crew members identified them as the pirates, although some crew have since said they are unsure of the hijackers' identities.
One of the defendants' lawyers, Martin Pradel, suggested that some of those arrested had simply been travelling in the vehicle when it was stopped and had no connection with the hijacking.
But Michel Quimbert, a lawyer representing the civil plaintiffs in the case such as the crew, said the evidence against them was strong.
The trial is to last until mid-June. A total of 22 Somalis are being held by France in connection with four hostage-taking incidents.