The Chinese search engine Sogou has filed for an IPO in the US as it aims to go public. Sogou, which is owned by Sohu and Tencent, aims to raise 600 million US dollars. Sogou claims that it is the second most popular search engine in China after first-placed Baidu, although this is disputed by another rival search engine Shenma which claims that it is the second most popular. Other data also shows 360 Search as a major search rival. What is not disputed is that Sogou's influence is growing, as it was recently integrated into the extremely popular Chinese social media app WeChat. Sogou generated revenues of 373 million US dollars in the first half of this year, up 15% on the same time period a year previously.