The “Unlisted” share option means that YouTube videos can only be viewed by people with the direct link provided by a creator. Content will also not appear in search results. Google in 2017 “rolled out a security update to the system that generates new YouTube Unlisted links.”
This update included security enhancements that make the links for your Unlisted videos even harder for someone to discover (if you haven’t shared the link with them). We’re now making changes to older Unlisted videos that were uploaded before that update took place.
Starting on July 23, Unlisted videos uploaded before the January 1, 2017, system change will be automatically made private.
We are also giving creators the option to opt out of this security update and keep their videos in their current state if they prefer. If you have a video that is impacted by this change, we’ll notify you directly.
That said, YouTube creators can decide to opt out of this change. Filling out this form will let you “keep your Unlisted videos uploaded before 2017 in their current Unlisted state.”
If you treat your Unlisted videos like Public videos (e.g. they’re embedded on third party sites or shared on social media), we recommend you opt out of this change. If you choose to opt out, your existing links will continue working as they do today, but they won’t get the benefit of the security update.
Other options include making Unlisted pre-2017 videos public or re-uploading as a new Unlisted video at the expense of stats:
You can also reupload these older videos as Unlisted under the new system to benefit from the security update. However, data associated with the original upload, like views or comments, won’t transfer. Any embedded videos using the old link would also need to be updated to the new video URL.
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