I came across an article dating from 9 December 2011 from Zscaler, where they mention that Opera uses Safe Browsing. I can't find any information that corroborates this. Does anyone know if that's true? Link: -http://research.zscaler.com/2011/12/switch-to-google-safe-browsing-v2.html There's also something interesting... or not ... The person who wrote the article made a test to see if Google's Safe Browsing would overlap other services such as MDL. They don't overlap each other, at all. Sure, some domains are blocked by all, but most are not. I never thought the difference would be... this different. Sorry for the redundancy.