(Corrects size of Qatar's UK holdings in paragraph 8)
LONDON/DUBAI, July 10 (Reuters) - Sovereign wealth fund Qatar Holding has sold 260.1 million pounds ($442.6 million) worth of shares in London Stock Exchange Group (LSE), a source familiar with the matter said on Thursday, ahead of the LSE's impending $1.6 billion rights issue.
Qatar sold the shares at 1,915 pence each as part of its portfolio management, the source said, adding that Qatar remained a supportive shareholder of the LSE. The disposal leaves Qatar with a stake of around 10.3 percent in the company.
The LSE is planning a rights issue of new stock to help fund its $2.7 billion purchase of U.S. indexes and investment management business Russell Group, the LSE's largest-ever acquisition, which was announced in June.
Qatar could use the money raised to fund the purchase of shares in the rights issue, to which it will be entitled because of its remaining shareholding, a further two sources close to the deal said.
The sale represents around 5 percent of the LSE's outstanding shares.
The price of the accelerated share sale was made at a 2.1 percent discount to Wednesday's closing share price of 1,956 pence. The original price range was set at between 1,845 and 1,925 pence.
Shares in the LSE fell on Thursday and were last trading down 2.1 percent at 1915 pence at 0816 GMT.
Qatar Holding said in a statement it did not expect to dispose of any further LSE shares in the immediate future. The fund's other British holdings include a 5 percent stake in lender Barclays, almost 26 percent of retailer J Sansbury and 1.8 percent of oil firm Shell.
Essa Kazim, chairman of Borse Dubai, the top shareholder in LSE Group with a 20.5 percent stake, told Reuters last month that the organisation was happy with the LSE's performance and had no plans to raise or lower its stake.
Qatar's sale was run by Citi and BoA Merrill Lynch .
($1 = 0.5877 British Pounds) (Reporting by Freya Berry and Clare Hutchison in London, with Andrew Torchia in Dubai; Editing by David Holmes)