During the May 2017 Build event's keynote, Microsoft announced a new feature called Cloud Clipboard that would allow data copied into the Windows 10 clipboard to be available to other devices that the user is logged into through the SwiftKey keyboard app. While originally announced for the Fall Creators Update, this feature never made it into the final update.
When Windows sleuth WalkingCat was taking a look at the Redstone 5 skip ahead build 17627, which is the next feature update being worked on for release after the upcoming Spring Creators Update, he noticed a string in the C:\Windows\SystemResources\TextInput\pris\TextInput.en-US.pri file that references the Cloud Clipboard feature.
17627: "You can share a small piece of text via clipboard and paste on any of your devices." Cloud Clipboard is coming, not sure if enabled, try Win+V ? OneClip lives @bdsams
— WalkingCat (@h0x0d) March 22, 2018

When this discovery was shared with another Window expert, Rafael Rivera, Rivera tweeted a screenshot of a Control Panel settings from Redstone 5 skip ahead build 17623. This clearly shows a new Clipboard settings section that is related to the Cloud Clipboard. It further shows that in the future, pressing the Windows key + V will open an application that displays a Clipboard history.

Digging down deeper into the TextInput.en-US.pri file, there appears to be another string that also references the upcoming Clipboard History viewer, which will allow you to view a list of recent items saved to the Clipboard.
You'll see your clipboard history here once you've copied something.
While the strings references to Cloud Clipboard remain, the Settings section has since been removed from the current skip ahead Windows Insider build 17627.
Bleeping Computer has reached out to Microsoft to get confirmation as to whether Cloud Clipboard is expected to be included in Redstone 5 and received the response "We’re excited to deliver this experience to everyone once ready.".
So at this point we will have to wait and see.

Comments
GT500 - 5 years ago
Is there going to be an option to turn it off completely?
Lawrence Abrams - 5 years ago
Looks like you can disable the automatic sharing.