BlackRock Inc (BLK.N) and State Street Global Advisors, the asset management arm of State Street Corp (STT.N), are among the firms that have bid for the business, three of the sources said.

The first round of bids was due in early October and the investment banking arm of Credit Suisse is representing its parent company on the deal, they said.

With 58 ETFs, Credit Suisse is the fourth-largest ETF provider in Europe, with 5.6 percent market share as of September 30, according to ETFGI, a London-based ETF research firm.

BlackRock is the largest ETF provider in Europe, with more than 40 percent of the $309 billion European ETF market. Its 192 European iShares ETFs had $126 billion in assets. State Street's 41 SPDR ETFs in Europe had $3 billion in assets, making up just 1 percent of the European market.

Credit Suisse's decision to sell its ETF business comes as the firm is closing or reducing other parts of its business to raise capital to meet new regulatory requirements.

Earlier this year, the firm said it was accelerating cuts in some of its asset management operations.

Spokeswomen from Credit Suisse, BlackRock and State Street declined to comment.

For BlackRock, the addition of Credit Suisse's ETF business would be the second international ETF business the firm has made this year. In March, BlackRock bought Toronto-based Claymore Investments from Guggenheim Partners LLC.

In an interview on Saturday in Tokyo , BlackRock chief executive office Laurence Fink told Reuters the firm was looking at a "fill-in ETF acquisition in another country."

(Reporting By Jessica Toonkel; Additional reporting by Katharina Bart in Zurich and Douwe Miedema in London)

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