Ok, I've read the court document:
http://cdn0.vox-cdn.com/assets/4490157/1-main.pdf
It... it actually looks like Zenimax has a case. From the paper it looks like Carmack and other Zenimax employees actually helped him build the original prototype by providing both hardware and software expertise they were using at Zenimax at the time. Before Zenimax, the paper claims that the rift lacked a headmount, VR-specific Software, integrated motion sensors, and other critical features and capabilities that Zenimax employees gave them. But they actually managed to get a non-disclosure at this point, apparently.
With the non-disclosure in hand, Zenimax then arranged demonstrations of the Rift prototype in the Bethesda booth at E3. Zenimax also says they designed the SDK and directed its development. After the success of E3, Luckey continued to rely on Zenimax employees for support and assistance and Zenimax began discussing appropriate compensation for their role in the hardware and software development as well as E3 marketing that played a vital role in the product's existence. They then began to get the cold shoulder as new investors swooped in and started buying the business from Luckey.
The document also confirms that Carmack signed away rights to anything he made that related to the Zenimax research and development during his employment which would have included any code he wrote for the Rift since Bethesda has VR research on hand from the 90's. They even include a quote from Carmack in that E3 conference referencing his VR research with Zenimax and Id Software. Zenimax had been developing/researching headset VR displays since 2011 with the number one problem being the latency which they'd been specifically working on since.
There's another quote from Carmack stating that Luckey sent him the optics and he added in his own hardware from the five headmounts Carmack already had in his office before getting Luckey's prototype. Carmack lists adding sensors, head strap, software and "stuff". They specifically came up with the low latency and specifically recommended the high-field of view.
Once Luckey started trying to commercialize the product, only then did Zenimax begin trying to discuss compensation.
There's even evidence printed to suggest that Carmack quickly worked to rewrite code after Zenimax's lawyers sent them letters this year. That his "line of code" comment is only true because he recently made it so in response to the allegations.
Frankly... if this is all true, then we actually owe a significant amount of gratitude to Zenimax. This is incredible. That they gave him all the technology at the start without demanding compensation is remarkable and generous even, but they did rightfully get a nondisclosure signed by Luckey and specifically reserved rights to their technology as protection for them letting Luckey go forward with the demo. I mean, if this is true the Luckey had very little to do with the product at all and this really is more Zenimax product than not. This paper indicates that he took all kinds of Zenimax hardware and software and ran it all the way to the bank. Oculus/Facebook's response will have to be epic to discredit any of this. They have backed up everything with direct quotes and have built a solid case. I feel a little guilty for being so strongly on team Oculus' side before the evidence really cropped up. I'm just glad I stated several times to wait on more information.