Hiscox's chief financial officer (CFO) of 16 years is to leave the specialist insurance group to join interdealer broker ICAP.Stuart Bridges, who joined Hiscox in 1999, will remain in office until the end of August and the search for a successor is already underway.Chairman Robert Childs said Bridges has made a "major contribution" to Hiscox, with gross written premiums rising from £241m when he joined to £1.76bn in 2014. The group's market cap also jumped from £240m to £2.50bn during that period."His steadiness under fire, particularly demonstrated in the aftermath of the terrible events of 9/11, testing hurricanes in 2005 and the financial crisis, has been of immense value to the group," Childs said.Bridges said he was "excited" about his new role but sad to be leaving Hiscox. He said: "I wish the board and the company well, and will be fully devoted to the group until my departure in the summer."ICAP's new CFO will be succeeding Iain Torrens who left in December 2014 to join Talktalk, with the role having been filled in the meantime by head of finance, tax, and treasury David Ireland."We welcome the appointment, noting the slightly extended period since Mr Torrens departure with the search having said to have been 'at an advanced stage' on 12 December," said analyst Paul McGinnis from Shore Capital.Both Hiscox and ICAP were trading down 0.3% in early deals on Monday.