Varun Singh, the CTO of Web18, is leaving the company, a source tells us. When we called Singh, he said only: “I haven’t put in my papers yet.” The source tells us that Singh is leaving to start his own company. This is a significant development for the company, which announced yesterday that it has filed for an IPO on Nasdaq. Singh is widely regarded as the key technology architect behind Web18’s portals and is credited with the success of In.com, the aggregator that is fast becoming Web18’s prized property. We will keep updating as we are get more information.