UPDATE 1-China Construction Bank holder selling stake

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HONG KONG, May 15 (Reuters) - An institutional investor in China Construction Bank (0939.HK: Quote, Profile, Research, Stock Buzz) is selling up to $372 million worth of its shares, according to a document sent to investors.

Amid concern that major shareholders plan to sell Chinese bank shares to take accumulated profit, the document said the unidentified investor was selling 408.5 million shares at HK$7.05 to HK$7.10 each, a discount of 1.8-2.5 percent to their HK$7.23 closing price on Thursday, in a deal handled by JP Morgan (JPM.N: Quote, Profile, Research, Stock Buzz) and Deutsche Bank (DBKGn.DE: Quote, Profile, Research, Stock Buzz).

China Construction Bank, the country's second-largest lender, went public in 2005 as part of a wave of IPOs by big Chinese banks that attracted strategic investors to their listings.

Lock-up provisions on stakes held by strategic investors, such as Construction Bank (601939.SS: Quote, Profile, Research, Stock Buzz) shareholder Bank of America (BAC.N: Quote, Profile, Research, Stock Buzz), will start to lapse this year, prompting market worries that subprime-battered Western financial firms will unload their stakes, putting share prices under pressure.

Singapore state investment agency Temasek Holdings [TEM.UL], which is the second-biggest foreign shareholder in Construction Bank after Bank of America, was not involved in Thursday's share sale, a source close to the deal said. Temasek sold $255 million worth of shares in China Construction Bank in November.

Bank of America, which has 8.2 percent of China Construction Bank, must hold its shares until October this year.

Hong Kong-listed shares in China Construction Bank have lost 18 percent since their peak in October but are still 208 percent above their Hong Kong IPO price in 2005. (US$1=HK$7.8) (Reporting by Kennix Chim, editing by Will Waterman)