No, it's not as simple as deleting lines that aren't yours or only reading the ones that are yours.
The only things that actually save ownership are the bricks that touch the ground. (ideally a baseplate)
The rest of the bricks do not save ownership.
When you load the bricks, bricks that don't have ownership will either:
-Acquire ownership of the baseplate, if there is none,
-Acquire ownership of the client loading the bricks.