The country's two premier stock exchanges, the Bombay Stock Exchange and the National Stock Exchange, are locked in a brand war to popularise their key indices, the Sensex and the Nifty-50, respectively.

While the Sensex is being marketed as "the index the world tracks," the NSE's Nifty-50 is being publicised as the "stock of the nation."

The NSE is 14 years old, whereas the BSE is Asia's oldest stock exchange, but only ten years separate the vintage of their indices. The Sensex started in 1986 and the Nifty-50 in 1996.

And here is the irony. NSE's turnover at Rs 9,029.51 crore is almost double BSE's Rs 4,541.76 crore. The NSE's index-based derivatives attract big trading volumes, whereas BSE's index-based trading is yet to start in a major way. The Nifty-50 generates daily trades of over 2,36,000 futures contracts to the BSE's paltry 4,244 trades.

But when it comes to brand recall and popularity, it is the Sensex that has the upper hand. Now, with both exchanges becoming the centre of global trading attention, their managements are trying hard to outdo each other.

The BSE has started a major initiative to attract big trading in derivatives based on the Sensex. It is asking members to trade more frequently on the Sensex futures, while the NSE is trying to overcome its weakness in the Nifty-50 brand by unleashing a major advertisement campaign.

"Many people trade on our Nifty index, but they talk about the Sensex. So, we thought we will make people aware of its benefits," said an NSE official, explaining the brand campaign. "Nifty-50 is a more balanced and diversified index," he added.

The BSE, meanwhile, is not sitting complacently. In a booklet recently circulated to the broking and investment community, BSE Managing Director and CEO Rajnikant Patel wrote, "Though most of the trading in index futures is done on the Nifty futures, investors are not gaining from the unique advantages that the Sensex futures contract offers."

So, why is it that the Sensex has more brand recall than the Nifty-50?

"It is only a perception. We hope to remove this perception through the campaign," the NSE official said.