It's easy to prove. Just go look at the number of iOS and OSX security fixes att...

jsjohnst on Aug 7, 2015 | parent | context | favorite | on: OS X sudoers exploit found in the wild

It's easy to prove. Just go look at the number of iOS and OSX security fixes attributed to him. Or you can go do a simple search on any reputable site posting security info and you'll see him all over it.