ICBC - the country's largest bank by assets, loans and deposits - has decided on an indicative price range of HK$2.56 to HK$3.07 (32.9 to 39.4 U.S. cents) a share, according to people involved in the transaction. That price range could still change slightly.

ICBC aims to sell 35.39 billion shares in Hong Kong and 13 billion shares in Shanghai. At the low end of the price range, the bank would raise $15.9 billion from the sale of those shares. But the share sale, like many, also gives the bank an "overallotment option" that could boost the number of shares sold by 15%, to 55.65 billion, fetching as much as $21.94 billion.

To grab the mantel of the biggest IPO ever, ICBC will have to raise more than the $18.4 billion NTT Mobile Communications Network Inc. raised in its 1998 IPO, according to rankings by market-data provider Dealogic Inc.

But demand for China's bank IPOs has been hot, and ICBC already has locked in $3.5 billion of demand from a handful of Hong Kong tycoons, including billionaire Li Ka-shing, several Chinese corporations and two Middle East investors, accounting for about a quarter of the value of shares being marketed to investors outside mainland China.

ICBC managers began formal investor meetings on Oct. 9 in Hong Kong and will travel the globe meeting with investors before setting the final price Oct. 20. The shares will begin trading Oct. 27.

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