* Price range puts value of Mail.ru at $4.78-$5.63 bln
* Pricing to take place on Nov. 8
MOSCOW, Oct 25 (Reuters) - Facebook's Russian investor Mail.ru has set a price range for its planned London initial public offering (IPO) at $23.7-$27.7 per share, a source close to the placement told Reuters on Monday.
The pricing would put Mail.ru's value at $4.78-$5.63 billion.
Mail.ru, whose placement might help set a benchmark for other Russian Internet firms, announced its intention to float on Oct. 11, with sources saying around 15 percent of shares could be up for grabs [ID:nLDE69A11C].
The company, previously known as DST, is expected to price the offering on Nov. 8.
In addition to a 2.38 percent stake in Facebook, Mail.ru owns 5.13 percent of e-commerce coupon site Groupon and 1.47 percent in social game company Zynga, as well as Russian mail and social networking sites and instant messenger ICQ.
Billionaire Alisher Usmanov owns 34 percent of Mail.ru. (Reporting by Olga Popova; Writing by Lidia Kelly; Editing by Will Waterman)