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Hi There 1. It could still be in the index because they are 302 redirect and not 301. 302 is temporary, and therefore Google may not de-index those URLs. It also takes time. I've seen Google take months to noindex redirecting URLs. Also, make sure you are not blocking crawling of the dev site, or Google will not see the redirects. 2. I am not sure how they got there to begin with. I pretty much always can find some sort of error - maybe someone tweeted a staging URL, maybe crawling wasn't blocked, maybe there was one link to staging from the live site etc etc. Regardless - somehow Google crawled it To prevent this in the future always block crawling of staging servers well before you ever put anything on them. 3. Usually Google tries to sort this out. They won't give you a penalty for "technical" duplicate content (penalties are more for "malicious" duplicate content ie: stealing people's content). So you won't get penalized, but the more you can help Google out by sorting it out, the more time Google can spend crawling the correct site etc. What I would do now is, if you do want the staging URLs to redirect (which might not be the best solution if you want to ever go back and work on the staging server again) - but if you do, use 301 redirects and make sure you are allowing crawling of the staging site. Keep it registered in webmaster tools and this way you can monitor the indexation levels.