in MagicDraw UML and MD SysML it is possible to have an element
contained in one Package / Model in the browser (in the actual model),
yet visually contained within the boundary of the rectangle of
a number of Components in any number of diagrams:

• If one moves any Element from a Package/Model to a Component in
  the browser the Component takes ownership.
• If one moves a Classifier from anywhere on a diagram into
  (within the rectangular boundary of) a Component in a diagram,
  that Component does NOT take ownership of the Classifier, the original
  ownership is preserved. A Realization relationship is generated between the visually contained Classifier this is
  what enables me to create "Class collaborations", and "composition views" of Blocks,
  Classes, and Artifacts without disturbing ownership.
• By contrast, if one moves a Comment on a diagam into (within the
  rectangular boundary of) a Component in a diagram,
  the Component takes ("steals") ownership.

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