Jan 22
18
Google’s John Mueller posted one of those PSA tweets this morning asking hosting companies that trigger robot detection interstitials to not use a 200 status code. John also said not to place a noindex on that page. If you do these things the pages served with these can be dropped out of the Google index and search results.
See the article here:
Google: Hosting Companies Should Serve 500 Status Code On Robot Detection Interstitial