Do search engines remove pages from the index for any 400 range status code return?

Question

Do search engines remove pages from the index for any 400 range status code return?

We are using 400 range HTTP codes to differentiate messaging for different categories of pages when a particular type of content is not found. There are some concerns that this content will not be removed from the search engine indexes as they would be if a proper 404 response is returned.

Has anyone used this method before to return customized error messages that can validate that these other codes are indeed removed from search engine indexes?

Answer 1

As far as I know: yes. I have some links to my site that generate a 400 status code, and they are not indexed in Google at all.

However as I mentioned in the other question, it's better to stick to defined status codes where possible, like 404 and 410 for missing pages.