LOCKUP command
The LOCKUP command is used lock the drawing into a whole block. You can't explode it or modify the objects of the original drawing. It is a good way to prevent others from modifying the drawing.
Command Access:
Command Entry: LOCKUP
Menu : Express tools>Drawing Tools>Drawing Lock
Once the command is started, the follow wizard will be displayed:
Select objects: Select all the objects in the current drawing to be locked and press Enter.
Note : Please save your drawing before using this function, because the locked drawing can't be modified.