Spaces always have only one owner. By default, the person that creates a Space is the owner.
If you have permission, you'll be able to change the Space owner from the Space settings modal, or from the Space settings page.
How does permission work?
If you're an admin or owner, you'll be able to transfer ownership of Spaces that you have access to, and you will have oversight of spaces from the Spaces page available on your avatar menu.
Inaccessible Spaces will be available to transfer if the owner of the Space has been removed as a member of your Workspace.
If you're a member, you are able to transfer ownership of Spaces that you created.
What does ownership mean in Spaces?
If you'd like to leave a private Space or hide it from your sidebar without deleting the Space, you'll need to transfer ownership first.
If someone else in your Workspace needs permission to delete or archive a Space, they'll need to be made its owner.
If you're a normal member who owns a Space, you will now have access to some additional features like changing the Space's icon/color and Custom fields.
How to Change Space Ownership
Click the ellipsis
...to the right of the Space you want to change ownership of
In the Space Settings menu click
All Space settings
In the Edit Space modal click
Search for or select a new owner
Transfer ownership of inaccessible Spaces
Workspace owners can transfer ownership of inaccessible Spaces.
Spaces can become inaccessible when they are private, and the person who created the Space is no longer part of the Workspace.
If another member still has access to a Space, you can temporarily make the person an admin so they can transfer Space ownership.
To transfer ownership of an inaccessible Space:
Click your Workspace avatar in the lower-left corner
Click the inaccessible Spaces tab
Click Transfer Ownership
You will now be the owner of the Space!