Cognizant Technology Solutions has extended its revenue lead over closest Indian rival Wipro in the September quarter of 2011, growing its quarterly revenues at double the pace of its competitor.

In the six months leading to September, Cognizant?s topline adds up to $3.08 billion compared to $2.87 billion of Wipro. On a quarterly basis, Cognizant had first displaced Wipro from the third position of India?s IT services pecking order during the June quarter of this year.

In the September quarter, Cognizant grew its revenues 31.6% over the year-ago quarter compared to Wipro whose topline increased 15.7% during the same period. Cognizant?s growth is impressive even when compared to bigger rival Infosys that grew 16.7% during the quarter.

Cognizant, in fact, beat all the top four Indian IT firms in terms of volume growth during the quarter. Cognizant raked in a sequential volume growth of 8.5%. The firm topped TCS, which reported a sequential volume growth of 6.25%, Wipro (6%) and Infosys (4.5%).

Its net profit stood at $227.1 million, up 11% compared to the year-ago quarter, Cognizant said while declaring its third quarter results on Wednesday.

Cognizant benefited from a continued momentum in offshoring and broad-based demand. The healthcare vertical jumped 42% while financial services grew 26% over the year ago period. Operating margins, however, contracted from 18.8% to 18.3%. It added more than 12,000 employees which included 4,000 from the company?s CoreLogic India acquisition.

?Cognizant has delivered another strong quarter of industry leading revenue growth with non-GAAP operating margins within our target range. Growth during the quarter was again broad-based across our portfolio of industries, services and geographies,? CEO Francisco D?Souza said.

?In spite of persistent macro-economic uncertainties, clients throughout the world continue to invest thoughtfully and strategically in their businesses and are directing investments toward building agility to drive the dual mandates of operational efficiency and business transformation. Cognizant?s continued investments across multiple service horizons help address these dual mandates and drive superior business value regardless of the economic environment,? he added.

Cognizant?s CFO Gordon Coburn said that the firm added 56 new customers and closed the quarter with 777 active customers.

Sanjeev Hota of brokerage house Sharekhan said, ?Cognizant has beaten street expectations on the topline. They have maintained consistent volume growth for many quarters and in this environment, these are definitely good results.?

It is unlikely Wipro will catch up with Cognizant any time this year ? unless through an inorganic move. The December quarter?s guidance suggests that Cognizant?s revenues would total $4.74 billion for the nine months of financial year 2012. Wipro, in comparison, would rake in $4.41 billion if the firm meets the higher end of its December guidance.

However, this does not mean that Cognizant can further increase its lead over Wipro. Aniruddha Mehta of IIFL feels that the gap between the two firms may not widen because Wipro has started performing well again.

?Cognizant has narrowed its revenue gap with Infosys, too. However, for the next two quarters, Infosys has given a guidance of 5.5% CQGR growth. Both Infosys and Wipro may start looking up from now on,? he said.

For the full year of financial year 2012, Infosys expects to generate $7.20 billion in revenues, up 19% over financial year 2011. Cognizant, in contrast, expects to grow 33% to $6.11 billion in 2011. The firm follows the January to December calendar.