[3] In 1976 Gandur joined raw materials trader Philipp Brothers (later Phibro) and worked for the company's Zug subsidiary for eight years.
[8] Gandur was named Commander of the National Order of Benin, has a diplomatic passport from Senegal, and was the honorary consul for the Republic of Congo in Geneva for ten years.
[9] Gandur, who works with international organizations as an art collector, participated in an interview regarding the correct provenance of objects for sale in April 2018.
[10] In January 2019, Gandur, together with other private donors and some countries, made a donation totalling USD 75,5 million for the safeguarding of cultural heritage sites in Iraq and Mali.
[11][12] Alongside ancient Greek and Roman works, Jean Claude Gandur's collection of Egyptian antiquities is one of the largest in the world still in private hands.
[14] In March 2010, Jean Claude Gandur made a commitment to the city of Geneva to invest 20 million Swiss francs in the renovation and expansion of the Musée d'Art et d'Histoire de Genève.
[24] In 2022, Gandur filed charges against unknown after discovering that the provenance of a Fayum mummy portrait he had acquired from the Pierre Bergé Foundation had potentially been faked.