A total of 41 portering staff - members of the Union des Commissionnaires de l'Hôtel des Ventes better known as the Cols Rouges - will stand trial for the organised theft of thousands of artworks they were tasked with moving from vendors' homes.
Six senior Parisian commissaires-priseurs (auctioneers) - including Claude Boisgirard, Hubert Brissonneau, Olivier Choppin-Janvry and Eric Caudron - will also be tried. They are accused of aiding and abetting thefts between 2006 and 2009.
The auctioneers all deny wrongdoing and insist that they too are victims of the Cols Rouges.
The Drouot Patrimoine, the company which owns the auction house complex, say they will stand as partie civile (civil plaintiff) in the case and will exercise their "rights as a victim before the French criminal court".
A statement on July 7 said: "Drouot is pleased to learn that the inquiry into the theft of art and precious objects commonly known as 'the UCHV affair' is now complete, and would like to commend the meticulous work of the police and magistrates.
"Drouot hopes that all the details of the wrongdoing will be exposed, and will deal with the consequences of any convictions that may follow."
Raid and Reform
The dramatic raid on Drouot premises in December 2009 rocked the Parisian auction system to its core and led to wholesale reform.
The French art crime unit Office Central Chargé de la Lutte contre le Vol et les Trafics d'Art had received a tip that one of the porters was seeking to sell a Gustave Courbet seascape, Paysage Marin Sous Ciel d'Orage, listed as missing in 2004 and valued at €900,000.
As more than 30 officers descended on Drouot, another police raid took place at Drouot's storage warehouse in Bagnolet, in the eastern suburbs of Paris. Over 100 containers were sealed as potential evidence. The homes of UCHV workers were also searched and a large quantity of drawings, paintings, watches and objets d'art were impounded.
The investigating magistrate Madame Anne Bamberger has put the total value of objects stolen between 2006 and 2009 at around €2.2m (£1.6m).
It is alleged that the Cols Rouges specifically stole from the estates of the wealthy deceased whose relatives had little idea of their possessions. The porters would later sell the objects at auction as their own property.
Expressing regret regarding its association with the Cols Rouges, the Drouot statement also announced the launch of a website designed to help "the many victims to identify the objects that were stolen from them and subsequently discovered in the containers of UCVH employees".
So far, almost 6000 items have been returned to the families who lost them.
What are the Cols Rouges?
The Union des Commissionnaires de l'Hôtel des Ventes, better known as the Cols Rouges on account of their red-collared uniforms, were Drouot's handling and transportation department.
The organisation operated as a closed shop composed of 110 men exclusively drawn from the Alpine region of Savoie, who enjoyed a monopoly of Drouot warehousing since Savoie was annexed to France in 1860.
Each of the 110 porters had a numbered uniform and an equal stake in the UCHV. Recruitment was by personal contact (and often family relationship) only. They each earned up to €120,000 (£86,500) a year for their services.
The 2010 Reforms
Faced with the biggest crisis in its history, the Hôtel Drouot, the central Paris auction venue, announced sweeping changes to how it was run in 2010.
• The Cols Rouges lost their monopoly on transport and warehousing and, following the French Justice Minister's scathing report about its culture and working practices, were later excluded from any future role. Drouot now employs several approved independent shipping and handling companies.
• For the first time in its 158-year history, Drouot appointed a paid chief executive. Former operations manager Henri Luquet, previously subordinate to Drouot's unpaid president, was given full executive powers. The new role of Directeur Général was supported by an elected management board composed of commissaires-priseurs (auctioneers).
• The Drouot promised to beef up checks on access to the building and increase video surveillance inside and out "as soon as possible".
• Drouot pledged that, to increase transparency henceforth all auctions would be transmitted live on the drouot.fr website.