* Offering twice subscribed at low end of f/c range
* Shares trade at 55 roubles, in line with IPO price
* Share sale values bourse at $4.2 billion
By Maria Kiselyova and Alessandra Prentice
MOSCOW, Feb 15 (Reuters) - Shares in the Moscow Exchange made their market debut on Friday and traded at around the offer price set in the company's flotation, marking a subdued start to Moscow's latest attempt to establish itself as a global financial hub.
The stock was changing hands at 55 roubles by 1241 GMT, bang in line with the price of the company's initial public offering which compared with a previously stated range of between 55 and 57 roubles, itself narrowed from an initial indicative range of 55 to 63 roubles.
The flotation of the exchange, Russia's main venue for trading in stocks, bonds, currencies and derivatives, raised 15 billion roubles ($500 million) after attracting demand for twice the number of shares on offer at the bottom-of-the-range price, boosted by support from a state-backed investment fund.
The IPO, carried out on the exchange's own platform, was politically and economically important in Russia after President Vladimir Putin made it an example of the sort of domestically-oriented share sale he wanted to encourage to boost Moscow's financial status.
The flotation of 30 percent of the exchange's equity, which valued it at 126.9 billion roubles, came as finance ministers and central bankers from the Group of 20 countries were meeting in Moscow.
"We proved that international investors are ready to come to Moscow if the asset is interesting," Moscow Exchange Chief Executive Alexander Afanasiev told Reuters after the opening bell rang out to signal the stock's debut.
Financial market sources told Reuters on Thursday the flotation had attracted foreign investors including China's sovereign wealth fund CIC, while Russia's state private equity fund RDIF also helped to fill the order book.
RDIF said it invested $80 million, becoming a 4.5 percent shareholder, and had attracted another $200 million to the flotation from other unnamed investors.
Speaking in a glass-walled office with views of the golden domes and Stalinist skyscrapers of Moscow's skyline, Afanasiev said the flotation had succeeded in attracting credible long-term investors.
"Firstly, it is about the quality of the investor base, we didn't want to lose some very good names that are currently our shareholders. Secondly ... they are also our future customers, the users of our market," he said.
The bourse will have a free float of around 30 percent.
"The listing of a stock exchange is always important for a country in the development of their capital markets," said an equity capital markets banker.
"There is obviously a wider goal to have more Russian companies list on their exchange ... this will be part of that and obviously helps show how it can be done by doing it themselves."
Credit Suisse, J.P. Morgan, Sberbank CIB and VTB Capital were acting as joint global coordinators and joint bookrunners of the offering. Deutsche Bank, Goldman Sachs, Morgan Stanley, Renaissance Capital and UBS were joint bookrunners.
The groundwork for the IPO was laid by improvements to Moscow's capital markets, such as the commissioning of a new central securities depository in November to simplify trading and settlement.
Afanasiev said further developments are in the pipeline to persuade foreign investors of Moscow's global standing, including plans to strengthen post-trading infrastructure and to introduce a new trading regime and derivative products.
Yet the long-term aim of building Moscow's financial clout may still rest on overcoming legal and corporate governance concerns, exemplified by the 2009 death in a Moscow jail of anti-corruption lawyer Sergei Magnitsky which has lately led to a diplomatic standoff between Russia and the United States.