I hadn't heard about OBC being unpatented, but then the Wikipedia pointed me to this email to the ietf cryptography forum: https://mailarchive.ietf.org/arch/msg/cfrg/qLTveWOdTJcLn4HP3...
So... yes... it looks like OCB is no longer encumbered.
I am curious why GCM was hard. Hard to do without side-channel leaks I can understand, but 800-38D seemed straight-forward.