Nikko Asset Management Co. began this week choosing lead underwriters for an initial public offering less than two years after Sumitomo Trust and Banking Co. purchased the firm, three sources said.

Nikko Asset is preparing to list on the Tokyo Stock Exchange as early as next March 31, the sources said. Sumitomo Trust will sell some of its stake in a global offering, according to the sources, who declined to be identified as the process is private.

The equity capital market has started to recover after share sales plunged in the wake of the earthquake in March. The Nikkei 225 stock average has pared losses since the disaster to 4.5 percent from as much as 18 percent, and Japan Airlines Co., Tokyo Metro Co. and Tokyo Stock Exchange Group Inc. are among companies looking to sell shares to the public.

Nikko Asset will conduct so-called beauty contests this month to select managers for the offering, the sources said. Spokeswoman Kyoko Wada declined comment, as did Sumitomo Trust spokesman Yasushi Kojima.

Citigroup Inc., which acquired Nikko Asset from Nikko Cordial Corp. in 2008, sold the company to Sumitomo Trust as part of a transaction that valued it at ¥120 billion in October 2009.

Nomura Holdings Inc., Goldman Sachs Group Inc., Citigroup, Daiwa Securities Group Inc. and SMBC Nikko Securities Inc. are among potential bidders to manage the sale, the sources said.

Since the quake, 28 Japanese companies sold shares in public offerings worth ¥240 billion in total, according to data compiled by Bloomberg. In the same period a year earlier, 35 companies sold stock worth ¥2 trillion.

Nikko Asset, founded in 1959, has 572 employees, including 72 fund managers, and has ¥12.8 trillion under management.