I think this is Rolf's wheel patent:
http://www.freepatentsonline.com/5931544.html
from there
Filing Date: 1998-08-06
Publication Date: 1999-08-03
I think patents last 20 years from filing date, unless this has changed, not sure am I. I think it may be a while.
As for the new Rolf wheels I've heard nothing but great things about them from everyone I talked to. Everyone I talked to said they never needed trueing or anything much less failure. The only caveat my LBS added is that they're expensive which is why they don't usually have models on floor. I don't have many miles on my Rolfs yet but I'd say so far that they're awesome. Best wheels I've ridden.