The promoters of Bharti Airtel are learnt to have acquired an additional stake of 0.5 per cent in the company, in a deal estimated at around Rs 8 billion. Meanwhile, Bharti Airtel's promoters have completed the purchase of 5.6 per cent of the 10 per cent stake that UK-based Vodafone holds in the company, thereby registering a total increase of 6.14 per cent stake in the company.