QIHU

Qihoo 360 Technology Co Ltd

A Chinese internet and cybersecurity company, Qihoo 360 is best known for its free security software — including 360 Safeguard, 360 Total Security, and 360 Mobile Safe — which protects hundreds of millions of users against viruses and malware, with revenue coming from advertising and other internet services. It was founded in 2005 by Zhou Hongyi, a serial entrepreneur who had earlier built the controversial search tool 3721, and his partner Qi Xiangdong. The "360" in the name signals all-around, 360-degree protection, and the company shook up the market in 2006 by giving away its antivirus suite for free when rivals charged annual fees.

American Depositary Shares — Delisted July 2016; privatized