Relationships between objects are stored in the object as a data member of AcDbObjectId class. There are four different types of relationships between objects—hard owners, soft owners, hard pointers, and soft pointers. For example, if you create an entity that requires a text style, that entity would have a data member of class AcDbObjectId, which would refer to an AcDbTextStyleTableRecord, and it would be filed out as a hard pointer ID. The way you file out the AcDbObjectId determines how the deep clone and wblock clone operations use the object ID. For more information, see Object References. Deep clone follows hard and soft owner connections, and wblock clone follows hard owner and pointer connections, as shown in the following figure:
