What's with UCEPROTECT List?

[Marc Perkel]

I'm having problems with my spam filtering servers getting listed on 
UCEPROTECT and can't figure out why. Is anyone familiar with how this 
blacklist works and what I need to do to not get listed?

They seem to hate sender verification - but I'm not going to give that 
up. What do I need to block to make my servers not show up on their 
list? This is getting to be more than annoying. What domains do they 
control so I can not trigger them?