I think the patent is too broad it could potentially prevent any company from putting any communication technology on balloons.

Plus how long should an NDA be preventing you from doing something you've been considering partnership with another company to do.

Any serious technology company would have iterated on their technology so much in 8 years that most of the information disclosed may not even be true any more.

It's also unclear weather any information gained by signing the NDA was actually used in the implementation of Project Loon.