The scenario I'm worried about may still be a valid concern under the new license.

Here is the scenario:

1. Google decides to buy my company in 2016.

2. They ask me to purge my codebase of React, so I switch to Angular.

3. Some years later, Google decides to sue Facebook over a blimp route optimization algorithm.

4. Facebook responds: "Well Google, one of your subsidiaries used React back in 2015 before you bought them, and now that you're suing us, that grant is no longer valid, so you're now liable for infringements on our React patents."

So with that scenario in mind, Google chooses to pass on buying my company, leaving some smaller acquirers, and maybe Facebook as possible buyers.

Please tell me this is not how it works. I would love to use React, but I can't bet the farm on this without more assurance.

IANAL, but my understanding is the termination is not retroactive. You would only be liable if you continued to use React after your patent grant was terminated.

INALIDEPLT: That is not how it works - a termination of the licences means your license is no longer valid, much like you can have any other agreement terminate but that doesn't mean it wasn't valid in the past. It would essentially be the same as if you had a license that was purchased for X years - you can't use it more than X years, but that doesn't mean you can't use it during that period.

Sorry it's a bit off topic but what does that acronym mean? Your post is the only result for it on Google!

I am not a lawyer I don't even play one on tv.

Also apparently I now rank on Google for something; that is pretty cool.

Edit: of course, I also fat fingered that one - the l should have been an o.

This is philosophical, really. You're extremely likely to be infringing patents already. If Google sues Facebook over a patent, the likelihood that Facebook can counter-sue over patent infringements is extremely high whether Google uses React or not.

It's called mutually assured destruction for a reason. Stockpiling patents as deterence is the most reasonable thing you can do in a system that allows software patents. It's the only thing likely to keep others from suing you over bullshit patents.