The Similarity Check service gives Crossref members reduced rate access to the iThenticate service from Turnitin. You receive this reduced rate access as you contribute to the iThenticate database of published content by providing full text URLs for this service in the metadata you register with us. If your content is behind access control and readers have to sign in before they can access your content, you will have safelisted Turnitin’s IP address when you joined the service to let them index your content.
Turnitin will be changing their IP address on 31st October, so you’ll need to safelist that new IP address before then to remain eligible for the service. Please note, you need to safelist that IP address in addition to the current one. We will confirm in the future when the old IP address has stopped being used.
Please whitelist the new IP range 188.8.131.52 to 184.108.40.206 as well as the existing range 220.127.116.11 to 18.104.22.168
Who needs to do this?
- If your content is available to readers without them having to login, you don’t need to take any action.
- If your content is behind access control or a paywall and readers can only access the content by logging in, you will need to add the additional IP address. Many of the platform providers are already looking after this for their clients, and we will keep this post updated with the platform providers who have confirmed this. If your provider isn’t listed or you aren’t sure, do check with your provider. If you aren’t using a platform, please check with your IT team.