Fabrico pens ARE permanent.
I had a class once in which the instructor explained that Permanent Ink markers were not actually permanent, however the Fabrico pens are. I can't remember exactly why the common Permanent markers are a problem, however she did mention it washing out.
Here is a link to the type I'm talking about
:
http://www.tsukineko.com/store/cart....duct_list&c=49