According to the announcement, “Posts that contain adult content will no longer be allowed on Tumblr, and we’ve updated our Community Guidelines to reflect this policy change. We recognize Tumblr is also a place to speak freely about topics like art, sex positivity, your relationships, your sexuality, and your personal journey. We want to make sure that we continue to foster this type of diversity of expression in the community, so our new policy strives to strike a balance.”
This new policy is expected to come into effect on the 17th of December, 2018. For users who have been using Tumblr to share explicit content, Tumblr will give you a heads up so that you have time to save those posts for posterity or to upload to somewhere else. Tumblr also mentions that they will be using automated tools to identify adult content, but warns that mistakes could happen and that certain posts might be flagged/removed incorrectly.
These changes seem to come on the heels of a report from last month where the Tumblr app was removed from Apple’s App Store where it was discovered that the reason behind its removal was due to child pornography.