Yahoo Inc. has sold its stake in China's Alibaba.com for $150 million, in a move that surprised Alibaba executives, according to media reports from Beijing.

Yahoo, however, said it is retaining its 39% stake in Alibaba Group, which is the parent company of Alibaba.com, a major e-commerce site.

Yahoo's investment in Alibaba.com proved to be timely, because shares are up nearly 50% since it made the investment. Alibaba management has had a particularly cordial relationship with ex-Yahoo chief executive Jerry Yang, who has been attending recent Alibaba celebrations in China.

Alibaba has been planning to build a presence in English-speaking countries including the U.S. and India.

The e-commerce site links sellers and buyers online as well as wholesalers and suppliers, although it hasn't been completing transactions. That could change soon as some executives in the company have indicated Alibaba may soon unveil a service that will permit Chinese exporters to complete transactions online.

Alibaba's founder, Jack Ma toured the U.S. recently drumming up support for the company's various units. Alibaba owns Taobao, China's foremost online auction site, as well as Alipay, an online payment system.

Jack Ma recently sold nearly $35 million worth of Alibaba.com shares -- representing less than 5% of his entire stake in the company. While the stock sales have attracted attention to Alibaba in recent days, the company noted that the expiration of lockup rules on stock sales has made it easier to sell Alibaba.com stock.

In addition to Yahoo, Cisco has also made a significant investment in Alibaba.

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