Anchor Text %

Anchor text penalty:

I understand that you should never go over 10% for kw but is it okay with the brand.
ie:
BlackHatWorld
http://www.blackhatworld.com/
www.blackhatworld.com


I think this is okay but just wanted to make sure. And how high can you go safely?

Thx

10% seems high.

Also: Don't forget blackhatworld.com and Black Hat World and so forth are also "brand" mentions.