Stock in Chinese search engine Baidu fell 6.8 percent on Tuesday after investment bank Credit Suisse downgraded the company to underperform. Baidu traded at $106.49 at the end of the day, down $7.80. Shares in the company briefly topped $150 about six months ago, but they have steadily dropped since then.

Bloomberg notes that Credit Suisse is the third bank to downgrade Baidu this month. Jefferies Group had dropped the company to a hold recommendation and Raymond James Financial had changed its rating to outperform, down from a previous recommendation of strong buy. A Baidu spokesperson declined to comment on the matter.

Investors appear to be largely concerned with a possible threat to Baidu’s core search business from upstart Qihoo 360. Baidu has enjoyed almost 80 percent of the Chinese search market in recent years with few credible challengers, especially after Google left the country. However, a much-talked-about search engine launch from Qihoo in August is shaking up the market. For its part, Baidu is actively competing against Qihoo, as the two have been engaged in back-and-forth blocking of each other’s services.

While investor concerns aren’t unfounded, Baidu does appear unlikely to suffer much from Qihoo’s entry into the market. Monetization is expected to be a significant issue for Qihoo’s fledgling search engine, and Baidu has a clear advantage from its size, scale and experience.

CEO Robin Li recently revealed that Baidu is investing 25 percent of its R&D resources into mobile. The company is deeply committed to its Baidu Cloud platform for Android and recently released a speedy mobile browser. Last month, it also announced a $1.6 billion investment in a cloud computing center.

Baidu posted revenues of $859 million during the second quarter of this year and is set to announce its third quarter results later this month.

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