I don't remember if the books talk about unbinding a focus that isn't the characters. For example lets say your character steals a power focus and wants to bind it to them.

Does the previous owner binding disappear as soon as the new owner binds it to them?
Does this mean that all the karma spend on that focus is gone forever by the previous owner?

Side question:
Why don't most mages insure their focus under a fade ID at the very least?

Can anyone else thing of any issues with this kind of situation? ... besides that the previous owner would use ritual sorcery to locate their own focus.

The mage just needs to bind with the foci. But he better do it quick or hide it behind a good ward, if he only stole it since the owner will be able to easily locate it.

The old binding is broken when the new magician spends the first karma point of the binding process. The new magician can then take his/her time to complete the process at his/her leisure. I believe the new link isn't formed until the binding process (the rest of the Karma) is complete.

I'm not aware of any rules for partially bonding with a focus. It's an all-or-nothing process; you spend (Force) hours then pay the Karma cost. Once you have, the old bond is broken and it is now yours to do with as you wish.

SR3 p. 190, Bonding.

Not entirely correct. Stacked foci can be paid for separately. P45, MitS

Well, yeah, but that's because they're basically just a bunch of different foci built into a single item.

OK? How about a mage needing to unbind a focus of his own?
For example, a mage with a physically large weapon foci needing to escape through a small tunnel or something. He is forced to leave his weapon foci behind, and wants to remove the trace link to him.

How would you go about unbinding the foci from yourself??

You go get the focus back and learn Severing to make it less dangerous until you can reclaim your property.

Severing is not a canon technique is it?

Either don't leave the sword behind or destroy it in astral combat. you just have to choose which is the lesser evil.

I believe this is one of the areas the rules never really go into, so you're pretty much left coming up with your own house rules until they do. I'd say a voluntary severing with a focus requires physical contact with it and a quick ritual (lasting [Force] Combat Turns just to give it a time limit so as to be a burden to try in the middle of a firefight) to release the bond should be good enough. It's not something you can do if you lose the focus, thus still keeping that as a liability for owning one, but it should be possible.

The focus would still serve as a sympathetic link, but it wouldn't be as strong as it would as a bonded focus and there would be no direct link between it and the magician any longer.

Add the caveat of having to pay full costs to rebond, and then that gives people pause about leaving a focus around. Come to think of it, it also gives you pause about even getting a focus. Better off summoning an ally spirit.

Don

That was assumed in my last post.

Yep. I sometimes harbor the opinion that tacitly stated things just don't work sometimes. This is where we get into "spirit" v. "letter" of rules in rules discussions. But yes, you're right.

Don

The enchantment on a focus can be destroyed by a mana combat spell while leaving the focus
itself undamaged.