David Balland, co-founder of the cryptocurrency company Ledger, was kidnapped in Paris and later rescued by the GIGN, a French special forces unit. He and his wife were abducted due to a dispute over an investment. Four men and one woman have been arrested in connection with the kidnapping, which reportedly involved a ransom demand of 40,000 euros. The arrests were made near Saint-Étienne, with two suspects apprehended at an airport by border police. The incident highlights the risks associated with the cryptocurrency sector, as it appears the woman involved was used to lure Balland to a meeting where the abduction took place.