State-run Coal India launched its $3.5 billion share sale yesterday, with its lower-than-expected pricing and exposure to India's booming electricity demand expected to draw solid investor interest to the country's largest-ever IPO.

Global investors in search of higher returns have been pouring money into emerging markets such as India in recent months. The Coal India offering is expected to draw billions of dollars in overseas demand that will add to upward pressure on the rupee.

Stock exchange data showed that at the end of the first day, bids had been received for a third of the more than 631.6 million shares being sold in the initial public offering.

If priced at the top of its 225-245 rupee price range, Coal India would have a market value of $35 billion, ranking it seventh among listed Indian firms.

It would surpass Reliance Power's $3 billion listing in 2008 as India's largest new issue.