The sale would ease concerns that Softbank could hold a monopoly on spectrum allocation designated by Japan's Communications Ministry, the source said.

Softbank, which is awaiting regulatory approval to buy a 70 percent stake in No. 3 U.S. mobile carrier Sprint Nextel Corp (S.N), bought Japanese rival eAccess last October as it stepped up competition with its nearest competitor KDDI Corp (9433.T).

Softbank turned eAccess into a wholly owned subsidiary on January 1 after a share exchange, using 220 billion yen ($2.47 billion) worth of its own shares.

After dividing eAccess shares into voting and non-voting shares, Softbank is considering reducing its ownership of eAccess voting rights to less than one-third, the source said.

Non-voting shares make up around 1 percent of overall shares. The sale of eAccess' voting rights would total several billion yen.

Other than Samsung, likely buyers include Sweden's LM Ericsson (ERICb.ST), Orix Corp (8591.T), the source said, adding that the eAccess voting shares would be divided between companies into hundreds of millions of yen each.

Softbank said on Saturday the news was not announced by the company and that it continued to mull options regarding its share holdings.

The Nikkei business newspaper reported earlier on Saturday that Softbank was also considering selling the eAccess stake to Finland's Nokia Siemens Networks NOKI.UL and five Japanese leasing companies.

Softbank cutting its eAccess stake would allow the company to work around the Communications Ministry's policy on spectrum allocation to telecom service providers and avoid suggestions of any monopoly, but still allow Softbank or eAccess to seek spectrum.

Under the policy, either a parent company, or one of its units in which it owns more than 33 percent, can apply for an allocation of spectrum.

Softbank will remain the top shareholder in eAccess but lose veto power after the sale, which is expected to close by end January and raise several billion yen, the Nikkei daily said.

(Additional reporting by Sagarika Jaisinghani in Bangalore, Writing by Mari Saito; Editing by Michael Perry)

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