It sounds HP's suit is based not on a non-compete agreement, but a provision of his $35M severance package in which he agreed not to disclose trade secrets or confidential info.
That's the impression I got from the article, anyway. I suppose it wouldn't be hard to argue that he can work for Oracle without disclosing HP trade secrets.
It seems to me that there are two possibilities, and either way, Hurd should win:
1. It is possible for Hurd to work for Oracle without disclosing HP trade secrets. Then Hurd is not breaching his agreement by working for them.
2. It is not possible for Hurd to work for Oracle without disclosing HP trade secrets. Then the agreement is a de-facto non-compete agreement, and therefore unenforceable.
I admittedly don't know the details, but if he has a severance, that usually implies that he was let go. All the non-competes I've ever read were effectively voided in the event of employer termination, unless the severance amount also included a non-compete clause itself.
I'm generally not a fan of non-competes, but if you get a $40m golden parachute, I think it's fair to ask that you not immediately jump to a competitor.
That's the impression I got from the article, anyway. I suppose it wouldn't be hard to argue that he can work for Oracle without disclosing HP trade secrets.