I think the wordplay is confusing you. Rift is the product name, but that's not how they're using it here. A "rift" is a disagreement. So the headline can be restated as "The disagreement related to Carmack about the Oculus goes to trial."

I'd blame the senseless title case that Americans use. If rift was lowercase, it would be easier to understand.

"Carmack rift over Oculus goes to trial"

It's intentionally written like that - it's a play on the word rift and the "Oculous Rift"

It's a pun. :)

Either: The rift over Oculus involving Carmack. Or: Carmack's rift over Oculus.