Sun Microsystems VIRTUALBOX 3.0.0 - Manual (Page 59)

3 Starting out with VirtualBox
Note: OVF cannot describe every feature that VirtualBox provides for virtual
machines. For example, snapshot information gets lost on export; the disk
images will have a “flattened” state identical to the current state of the virtual
machine, but any snapshots that were defined for the machine will have been
merged.
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