The same pattern has emerged in the case of Wednesday's merger announcement of UTI Bank and Global Trust Bank (GTB).

Both the counters have witnessed huge volumes and sizeable rise in prices before the merger was officially announced. The sudden spurt in volumes has raised eyebrows and sources watching the developments have expressed the view that even this is an apparent case of informed buying and requires a threadbare probe by regulator Securities and Exchange Board of India (Sebi).

On Wednesday, the GTB stock hit the two upper circuit limits of 8 per cent each on the Bombay Stock Exchange (BSE), and was locked at Rs 93.95. The trading volume pattern of these two stocks also shows a marked rise mainly on the BSE, while the volumes spurt is not that pronounced on the National Stock Exchange. The question now being asked is: did someone trading on the BSE know more than the others in the rest of the market? The price movement of these two stocks have shown an interesting pattern since the beginning of the new year, with considerable increase in volumes at both this counters.

Global Trust and UTI Bank were attracting meagre volumes till the first week of January, but trading volumes have picked up with average daily volumes on the Global Trust Bank counter increasing from 20,000 shares at BSE to 1,57,000 shares on January 24, while at NSE the trading volumes have jumped fourfold from 15,000 shares to close to 67,000 shares. The price of this stock has also increased from Rs 81 to Rs 94.

Even in case of UTI Bank, the story is identical. The trading volumes at BSE have risen from 34,000 shares to 2,58,000 shares on January 24 while on NSE the volumes have shot up five times from an average of 45,000 to 2,70,00 the stock price have marginally increased from Rs 45.75 to Rs 49.85.