* Hong Kong approval has long shelf life
* Next key step is intention to float document in London
* Asian billionaires, trading partners likely to invest
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By Denny Thomas and Fiona Lau
HONG KONG, April 1 (Reuters) - Glencore International AG, the global commodities trader, has got approval to list from Hong Kong's stock exchange as it prepares an initial public offering which could raise $10 billion, sources said.
The Hong Kong stock exchange approval -- according to sources with direct knowledge of the matter -- does not stipulate any deadline for Glencore to launch the IPO, but it is an important step towards it.
Glencore is considering a dual listing in London and Hong Kong. Amid recent market turmoil Hong Kong's approval is the strongest hint yet that the company will still proceed.
Glencore declined to comment.
Glencore's listing application was considered by the Hong Kong exchange at a scheduled meeting on Thursday.
Glencore, valued earlier this year by one analyst at about $60 billion, is looking to ditch its long-standing partnership structure in favour of continuing as a public company, which would make it easier to reward partners and conduct acquisitions.
The company has kept its listing plans under wraps since briefing analysts last month. It set an April 1 deadline for the sell-side analysts it briefed to complete their research notes.
Glencore is not required to come back to the Hong Kong listing committee unless there are material changes to its situation.
The next key step is the release of Glencore's much-anticipated intention to float document in London, expected by some sources to follow on the heels of the Hong Kong stock exchange approval.
The London leg of the IPO will take longer to complete.
The sources declined to be identified as the IPO discussions were confidential.
A Hong Kong exchange spokesman declined to comment.
CORNERSTONE INVESTORS
Glencore has met with several key potential investors from Asia to the United States to gauge interest for the IPO and the response has been positive, sources previously told Reuters.
If it decides to proceed with the offer, Glencore will aim to launch the retail portion of a Hong Kong IPO in the third or fourth week of April, with a listing scheduled for early to mid May, sources said.
Asia's biggest sovereign wealth funds and some Hong Kong billionaires are seen as likely to invest in the IPO. Such so-called cornerstone investors are common to many large Asian IPOs and are assured a significant portion of the float.
Cornerstone investors usually have a lock-in period of up to one year. They bring more credibility to the IPO, which in turn helps the underwriters to generate more demand for the offer. (Reporting by Fiona Lau and Denny Thomas; Editing by Chris Lewis and Sophie Walker)