Baidu's credibility on the line after search results lead to student death

Baidu is facing an investigation from the Chinese government after a student died after seeking experimental treatment, found via the search engine, for the rare cancer he was suffering from.

Wei Zexi underwent a type of experimental cancer treatment at a Beijing hospital after noticing a paid advertisement on the top of his Baidu search. Wei died last month of a rare form of cancer. The treatment cost his family 200,000 yuan and wasn't successful.

Before dying, Wei accused Baidu online of promoting false medical information, as well as the hospital for misleading advertising in claiming a high success rate for the treatment, state radio said.

Medical advertising makes up about 30% of Baidu's ad revenue, and about half of that comes from a private hospital union called Putian Healthcare Industry Chamber of Commerce. This union signs so called "master contracts" with Baidu every year committing to grow its advertising spending by 30-40%.

China has strict laws against false advertising in medical products, but how they apply to online search results is not clear. It also is unclear whether the promoted link that Wei followed was in fact misleading.

"Companies that were involved in services that deal with human life should be particularly conscientious of their duties when conducting their businesses," the website of People's Daily, the Communist Party's flagship publication, wrote in a commentary that questioned Baidu's corporate ethics.

"Billions of net users trusted Baidu for their search engine and online forum services, the company is hence responsible for the trust and is obligated to taking up their social responsibilities."

Government and military health authorities have announced a separate investigation into the hospital, as the state news agency Xinhua reported.

Baidu stock fell 8% on Monday after China announced it was launching an investigation into the company.