Modify > Clone
This feature is available from the Modify Menu of all assets that have an identifier/URI. It produces a new asset that has the same property values as the currently selected asset, but a different identifier (URI). It opens a dialog where you can enter that new identifier.
Caution
This operation currently does not work well on classes, as it will not clone the property declarations. You will instead end up with multiple classes that share the same property declaration instances, likely causing issues later in the development. It is typically better to create a fresh new class and then use Modify > Clone property shapes from to give that class its own property declarations.
See Also
Further Reading on Modify Menu
Further Reading on TopBraid