It's likely Intel's already got cross-licensing agreements for everything they need, seeing as they already build GPUs. (Or is somehow everyone forgetting that fact?)

The case is probably that the Intel graphics team just decided they'd rather play against the big boys at nVidia and actually put enough cores on a chip to be a competitor, but in order to do that, they'd need to go off-chip for power and heat dissipation reasons. Hiring the guy from AMD helps you sell the new solution, since presumably that's what this guy's good at.

The market's rife for being disrupted as it has been incredibly stagnant with nVidia and AMD's tit-for-tat for the past, well, decade.

Intel has a both a large patent portfolio and a lot of legal firepower in that space, so no, I don't think folks like Nvidia will be able to "threaten" Intel with patents. Nvidia might be able to threaten them with the monopoly card (clearly Intel is using its dominance in desktops and laptops to move into an adjacent market) but they have been doing that for many years with the integrated GPUs so I would expect it to be a weak play.

Maybe Raja's move was part of the AMD Intel GPU deal, as could be some undisclosed fees for use AMD graphics tech for use at Intel. That could mean Raja is there to lead a close integration of the tech bases.