New Delhi, Oct. 24 -- The decision of Infosys Ltd's promoters to opt out of its largest buyback of Rs.18,000 crore points to an underlying concern, that of tax.

Promoters of the country's second-largest information technology (IT) services company, including founders Nandan Nilekani, N.R. Narayana Murthy, S.D. Shibulal and S. Gopalakrishnan would have to shell out more tax and earn less money in hand if they were to sell their shares through the buyback than through the stock exchanges. Currently, the promoters and their group own 13.05% of the company's shares.

On 11 September, Infosys announced that it would repurchase 100 million shares at a price of Rs.1,800 per share. It ended Thursday with a share price of Rs.1,529 per share, whic...