Fillon is getting his boxing gloves on in preparation for a newly-announced run at France's presidential elections in 2017.
They are joined by compatriot Valérie Pécresse, centre-right deputy for the Paris suburb of Yvelines and former UMP spokeswoman under Fillon's tenure as PM. Pécresse is a known supporter of Fillon, who in turn has mentored her in her career.
The La Tribune newspaper also reports that the French envoys to Watford also include Axa CEO Henri de Castries and Michelin CEO Jean-Dominique Senard.
They will be joined by Nicolas Barré, editor of the business journal Les Echos, as well as the commander of the Eurocorps military Olivier de Bavinchove.
While La Tribune commented that the French delegates will likely debate the state of the economy with the other attendées, the closed-door policy of the event, which started in 1954 to foster North American-European dialogue, has raised some eyebrows.
"It's reasonable to bet on the 2013 edition once again provoking controversy and feeding conspiracy theories in certain circles," the paper noted.
It is a group that in its odd juxtapositions - mixing European royalty with politicians from all quarters - has fueled its fair share of fevered suspicion, this year no less than others.
Britain's conservative Daily Telegraph heavily featured a photo showing Lagarde affectionately patting George Osbourne, British Chancellor of the Exchequer, on the shoulder.
More than 120 delegates assembled on Thursday at the Grove Hotel, in Hertfordshire north of London, reportedly to discuss an exhaustive list of topics including economic growth, employment, debt, the EU, Africa, and Middle East, while also looking at US foreign policy and developments in medicine and IT.
Left-leaning French weekly Le Nouvel Observateur said that some sceptics have chosen to call the Bilderberg Group "the real world government", which conspiracy theorists credit for everything from US President Bill Clinton's election to the US-led invasion of Iraq.
Its original goal, however, was to unite leaders from both sides of the pond against the threat of communism.
"At the time, the goal was to convince European and American leaders to make closer ties and not let their guard down against the power of the Soviet Union," former Foreign Minister Hubert Védrine told Le Nouvel Observateur.
Being invited to the Bilderberg group, named after the first hotel where the delegates met in the Netherlands, is considered a mark of esteem.
Reportedly, Fillon declined to take part when he was in office as prime minister. He has also said he has little sympathy for those who think that conspiracies are woven behind the doors of the meeting, which changes venue each year.
"I don't understand the hysteria surrounding Bilderberg. I don't feel that people say things there that are very confidential," he is cited as saying by Le Nouvel Observateur.
While rumour has it that a Bilderberg member and US Democratic Party silver back Vernon Jordan in 1991 plucked then Arkansas governor Bill Clinton out of his relative obscurity to later propel him onto the national stage, it remains unclear what Fillon's attendance at this year's meet may entail in terms of any real progress on home turf.
Whether his participation will further his presidential ambitions or not, he may need all the strength he can muster as the mudslinging between himself and former conservative President Nicolas Sarkozy, who may want a second bit of the presidential cherry, has already gotten underway.
Fillon has nicknamed Sarkozy the Duracell bunny, but that 'bunny' retorted by calling his former PM a loser.