To those that are commenting it was an early stoppage I will explain, the logic is as follows:

If you cannot intelligently defend yourself the fight will be stopped.
Grabbing the fence is illegal, they are informed of this before the fight begins, this has been drilled into them again and again.
The fighter has been compromised, he has made two (2) flagrant fence grabs to improve his position, had he not grabbed the fence he would have continued to stay on the bottom and incur damage where the fight would have ended. Additionally if you do not have the wherewithal to not drag yourself to your feet via the fence you are not all there mentally.
Compounding this the disruption to the fight was too great, if he had to separate them he it would have been too big of a momentum shift, Derrick would've been tired and the Brazilian would have got a rest.