I think the news blurb pretty much sums up everything.
AI bought out ALL rights and interlectual property with regards to AMIGA. That includes OS and property and anything else related. Just because they get Hyperion under contract to develop the next version of the OS doesn't mean Hyperion own it. They are contract developers. AI could have got SUN or TAO or any number of software houses that can program to do the work on it, I guess because Hyperion had experience in the field, they seemd the most logical choice.
Don't get mistaken though, AI own the OS. Hyperion are under contract to make it for them unless there is something very different about the contract they signed.