Nvidia has pretty much confirmed the existence of the long-rumoured Nexus 9 tablet which HTC is manufacturing, as it mentioned the slate in some legal squabbling.
Nvidia currently has a patent lawsuit on the boil against Samsung and Qualcomm, and in a legal filing pertaining to this case, the company directly mentioned that the slate would be driven by its Tegra K1 processor (as has been previously rumoured).
The Inquirer reports that the document in question stated: "The HTC Nexus 9, expected in the third quarter of 2014, is also expected to use the Tegra K1."
While Q3 would date the launch of the tablet as September – in the next couple of weeks, in other words – it's likely that this has slipped somewhat (the use of the word "expected" being a clue there, too).
Still, it seems that HTC is indeed making the 8.9in tablet, the other rumoured specs of which are a 2,560 x 1,600 resolution display and no less than 4GB of RAM, with an 8 megapixel camera (or possibly 5 megapixel – tablet cameras aren't a massive priority, of course, as plenty of folks aren't keen on snapping in public with a giant slate for obvious reasons).