Mumbai: WNS, EXL and 24/7 are a relieved lot. The three BPOs have managed to retain business from one of their largest customers - UK's largest insurance company Aviva. Sources say the deal which will see them gaining control of Aviva's captive unit Aviva Global Services which is worth more than $1 billion over the next 10 years. Aviva gets its insurance and IT processes done out of locations in India and Sri Lanka. Aviva had adopted a build, operate and transfer strategy for off-shoring. Three vendors - WNS, EXL and 24/7 - were to start new offshore facilities, recruit and train staff and then transfer the entire operation to Aviva's own captive unit - Aviva Global Services. In January 2007, Aviva kickstarted the transfer by acquiring 24/7’s 1600-employee strong facility in Bangalore. WNS' 300-people facility in Sri Lanka followed. But, then sources say Aviva realised it would be better letting the experts manage off-shoring. Responding to an email questionnaire by CNBC-TV18, Aviva Global Services said, "As we have indicated, we've been reviewing our options with regard to our offshore operations and that review is now coming to a close. We expect to be able to announce our decision shortly and will let you know as soon as we have further information to share with you" While EXL and WNS did not offer any comment, 24/7 didn't respond to CNBC TV18.