Last week the same question below came in from several users.
“I copied a Class and pasted it on a diagram. But when I modified the copied class, the same change applied to the master copy. Can’t I produce independent models by copy & paste?”
You can create a new model based on existing one by copying but you will have to use ‘Clone’ instead of ‘Copy’. You can find this [Clone] menu in the Structure Tree (Top left pane.) ‘Clone” copies the model and its attributes. Following figure shows cloning a Class A.
On the other hand, ‘Copy’ menu copies its presentation only, not the model itself, so that when you make changes to copied model, the same change applies to the master copy. Following figure shows what ‘Copy’ menu does.
Hope this clarifies the difference between ‘Clone’ and ‘Copy’.