Break permission inheritance in SharePoint
Now you've got to the Permissions page. Next, you will need to break permission inheritance before you can assign unique permissions, change permissions levels, or remove user permissions to a list, library, or survey. When you break permissions inheritance for a list, library, or survey and then define new permission settings, the list (or library) becomes a parent for items in it. Items under that parent now inherit the new permission settings (unless the items have uniquely defined permissions.)
To break inheritance and assign unique permissions, follow these steps:
1. Go to the list, library, or survey and open it.
2. Go to the Permissions page using the steps in the previous section .
3. To break permissions inheritance from the parent, select Stop Inheriting Permissions .
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