I can only speculate, but as you may recall, Numenta abandoned their original, belief-propagation-based design, replacing it with a new one based on sparse dist

I can only speculate, but as you may recall, Numenta abandoned their original, belief-propagation-based design, replacing it with a new one based on sparse distributed memory. Dileep had done a lot of work on the original design, and I recall reading that's what Vicarious is using, having licensed it from Numenta. So I think you can put it down to a difference in technical direction between Dileep and Jeff. As far as I know, the split was amicable.