This seems to be an arbitrary limitation you are applying. Most specialized machinery requires highly-skilled workers. They are effectively useless without the right person operating (executing) the machinery.

Regardless, my original point still stands: it is their duty to return as much money as they can to shareholders/investors. Someone is willing to buy their patent portfolio, therefore they are selling it.

Why are you trying to assign morals to something as simple as an exchange of assets in a market?

(This isn't arguing for or against the idea of patenting these technologies...that's a different can of worms. But as it stands, they A) have patents and B) are capable of selling said patents.)

  An idea or patent is utterly worthless without execution

No it's not. In this case it's worth $525m. Clearly other people assign value to them, even if you don't.

In a world where ideas weren't patentable, they'd be worthless. For better or worse, the current US system says that ideas don't have to be executed in order for patents to be granted. Patents are valuable only because the current system says they are.