General Atlantic, the US private equity firm, is considering an IPO of Xchanging, the UK-based outsourcing and processing business that ranks as one of its largest European investments. People familiar with the matter said Xchanging, which General Atlantic formed in 1998, had been in discussions with a number of investment banks about a flotation on the LSE that could value the group at about £500m. However, they cautioned that those plans could still unravel. An IPO would allow General Atlantic, a frequent investor in technology businesses, to begin monetising its ownership of Xchanging. However, even after a flotation General Atlantic is not likely fully to withdraw from exit its investment in Xchanging for a considerable significant amount of time, people close to the matter said.