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Alipay is the preferred online payment tool of Internet merchants due to its innovative product technology, unique concept and large user base. In addition to Taobao and Alibaba.com, Alipay provides payment solutions in China for more than 500,000 external merchants for online retail, virtual gaming, digital communications, commercial services, air ticketing and utilities fee payment transactions.

Market shares of 3rd party online payment companies
(2011Q1 by iResearch)

As of December 2010, Alipay had more than 550 million registered users and facilitated around 8.5 million transactions daily

Histogram of membership growth