UPDATE 1-Alibaba, Softbank team up on China-Japan platform

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SAN FRANCISCO/HONG KONG, May 14 (Reuters) - Alibaba.com Ltd (1688.HK: Quote, Profile, Research, Stock Buzz) and Softbank Corp (9984.T: Quote, Profile, Research, Stock Buzz) teamed up on Thursday to form a joint venture that links small corporate buyers and suppliers in Asia's two largest economies, marking a pivotal overseas foray for China's largest e-commerce firm.

The Hong Kong-listed arm of privately held Alibaba Group said Japanese Web and telecoms group Softbank would invest $20 million initially into the venture for a 65 percent stake, with the listed Chinese firm holding the remainder.

To be called Alibaba.com Japan, the new firm will take over the operation of Alibaba.com's existing Japanese language site and target small to mid-sized businesses, aiming to connect them to a global trading platform.

Alibaba -- which says it has built a community of close to 30 million members from over 240 countries and regions since its 1999 inception -- is trying to expand its presence beyond home turf China, which houses the world's largest Internet population.

It has also sealed an agreement with India's Infomedia to develop an online trading platform for Indian corporations.

Softbank, which already owns 30 percent of the Alibaba group, has in turn been actively seeking investment opportunities across Asia.

"Alibaba.com Japan will provide Japanese businesses with the most comprehensive database of suppliers available online today from China and around the world," Alibaba Chairman Jack Ma said in the statement.

Shares in Alibaba fell 0.8 percent on Thursday afternoon, in line with a sliding market .HSI, with investors having expected the venture's formation since discussions with Softbank started last year.