Plans supporting this feature: Professional Business Enterprise
The Block inheritance feature allows you to restrict content access for users, even if they have inherited permissions from a higher content level. With this, you can prevent users or teams from accessing certain content, regardless of their inherited access rights. This would allow only specific users and user groups to access a content level (workspace/language/category/article).
Content access at Workspace level
For example, you have six inherited users in workspace V1 and want to provide access only to one user and yourself.
Navigate to Settings () > Users & permissions in the left navigation bar in the Knowledge base portal.
In the left navigation pane, navigate to Content access.
Select the required workspace & language.
Turn on the Block inherited account toggle in the Manage content access tab.
Now, all the other inherited users that cannot access workspace V1, will not be displayed and only those users that have content access will be displayed.

Deactivate inheritance for a category or an article
Navigate to Documentation () and hover the mouse pointer over the desired category/article in the Articles & categories pane.
Click on the More () icon that appears next to the category/article name.
Click on Security, then choose Knowledge base portal Access control.

The Assign control access: Knowledge base portal panel appears with the list of users and user groups that have access to the selected content level.
Turn on the Block inherited account toggle, and only the accounts that are not inherited will display.
By default, the user performing this action would be selected and cannot be removed.
Click on the Assign article access to provide content access to a specific user.
Select one or more users and click Apply.
Once you have made changes, click Close.

What happens after removing inheritance?
After removing inheritance at the content level, only users and user groups in the content access list can access that content level (workspace/language/category/article). Later, you can also provide access to the desired users and user groups.
Allow inheritance
If you want to provide access to all the inherited users and user groups, turn off the Block inherited account toggle.
Enable inheritance for a category or an article
Navigate to Documentation () and hover the mouse pointer over the desired category/article in the category manager.
Click on the More () icon that appears next to the category/article name.
Click on Security, then choose Knowledge base portal Access control.
The Assign control access: Knowledge base portal panel appears, showing the list of users and user groups that have access to the selected content level.
Turn off the Block inherited account toggle and click Yes in the Allow inheritance prompt.
Once you have made changes, click Close.

FAQ
What happens when I deactivate inheritance for a category or article?
When you deactivate inheritance, only the users and groups listed in the content access list can access that category or article.
Is the user performing the action automatically selected when blocking inheritance?
Yes, the user performing the action will be automatically selected and cannot be removed.