Command entry:Select a group.
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Group menu
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Open
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Select one or more objects to detach.
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Group menu
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Detach
Command entry: Scene Explorer 
Right-click a member of an open group.
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Groups
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Exclude From Group
The Detach (or, in Scene Explorer, Exclude From Group) command detaches the selected object from its group.
This command becomes available when you select a member of an open group.
Procedures
To detach an object from a group:
- Open the group.
- Choose Group
Detach.
The selected objects are now separate, independent objects, no longer members of the group.