Hey Moz Community! I've been digging into the differences between server-side testing and client-side testing and had a generic question. Is it safe to run server-side A/B testing? For example, if I want to Split Test the home page of a site and show 50% of my traffic one home page, and show 50% of my traffic a completely different (read: new template, new content, new CTAs, etc) home page, are there any implications to SEO and organic search? I've spent about five hour researching and from what I can find A/B testing is acceptable as long as you don't show Googlebot different content or run A/B tests on Googlebot. Matt Cutts, head of Webspam at Google, has stated that A/B testing does not impact search rankings. "A/B or split testing or other forms of testing web sites is okay by Google as long as you don't test GoogleBot or don't treat GoogleBot differently." The biggest concerns for SEO cloaking, so from my understanding, for server-side testing, you'd need to do user-agent based redirection so that Googlebot (or any search bot) gets the normal version of the home page. The bots shouldn't be part of the test. Technically that is cloaking, but intention-wise, we're not trying to be sneaky. I've also read through this article about experimentation from Google developers here. Am I missing anything here or is there a definitive answer? If we serve a “B” as a different site for user testing, just exclude google bot by user-agent and we’re good? THANKS!