Wake up. Sun was assigned the trademark in the USA *after* it had been registered by a private group. This was done so that there would eb sufficient resources to enforce the trademark. Sun was than tasked by the OO.o community to register the trademark in the rest of the world, since they were the only part of the community who had the resources to do so.
When Oracle bought Sun, they inherited the ownership of said trademarks.
As for the "Document Foundation", I personally as a long term member of the OO.o community (since before version 1.0 was released, actually) see their behaviour as that of a spoilt child who couldn't get its own way.
Yes, there is a need for a foundation, but I disagree totally with the way this was done. It looks sneaky and underhanded from where I sit. And no, I do not, and never have, worked for either Sun or Oracle (I happen to be retired, and have lived in Australia my entire life).