SAN FRANCISCO, United States — Index Ventures, a backer of "Candy Crush Saga" maker King Digital Entertainment Plc, is planning to raise 350 million euros ($487 million) for an early-stage fund, said two people with knowledge of the matter.

The London-based venture capital firm will cap the new fund at 400 million euros, said the people, who asked not to be identified because the fundraising is private. Index unveiled its last early-stage fund, focused on growth technology and life sciences startups, in June 2012.

Started in 1996 by brothers Neil and David Rimer along with Giuseppe Zocco, Index has expanded in recent years beyond its European roots in London and Geneva to establish a U.S. presence. The San Francisco team includes Mike Volpi, a former Cisco Systems Inc. senior executive; Danny Rimer, a brother of the founders; and James Higa, who helped create Apple Inc.’s iTunes music store.

Venture capitalists are ramping up fundraising following a year that saw at least 10 firms return $1 billion or more to their investors. Founders Fund, a venture firm run by PayPal co- founder and early Facebook Inc. investor Peter Thiel, announced the close of a $1 billion fund earlier this month.

Amy Sezak, a spokeswoman for Index, declined to comment.

Supercell, Criteo

Index’s most successful deals have been in Europe. The firm generated returns last year from an investment in Helsinki-based gamemaker Supercell Oy, which sold a majority stake to SoftBank Corp., and Paris-based Web-advertising company Criteo SA, which sold shares to the public in October. Index’s holdings in Criteo are worth more than $550 million.

Index owns a stake worth almost $600 million in King, assuming the Dublin-based online games company prices its initial public offering at $24 a share, the top end of the projected range.

With the exception of about 583,000 shares that Index is divesting in the IPO, the firm is restricted from selling for six months after the offering. Zynga Inc., another online gamemaker, dropped 44 percent in the six months after its Dec. 2011 IPO.

Other Index investments include cloud-storage company Dropbox Inc., food order service Just-Eat and mobile news application Flipboard Inc.

By Ari Levy, Sabrina Willmer; Editors: Pui-Wing Tam, Christian Baumgaertel, Reed Stevenson