No it is NOT identical. In situation A/C (React is licensed under BSD + PATENTS), you have explicitly agreed to have what is essentially your lawful use of React immediately revoked if you sue Facebook for patent infringement. So you sue Facebook, and whether or not your suit is of merit: You have to immediately stop using React. This actually prevents people who are dependent on React from suing Facebook for patent infringement, since they'd basically have to remove any dependency on React before suing. And this emboldens Facebook to infringe on the patents of entities who have a dependency on React, where it would be a major undertaking for the React-dependent organization to cease the use of react. Remember, Facebook is saying they have this in place to prevent merit-less legal battles. But the way they've set it up, it's not a question of whether your suit has merit or not. Facebook is saying "Sue us for patent infringement, and you immediately give up your use of React. Period." So the court rules in your favor over an unrelated patent infringement case? Congrats you won that case, but you've still given up your use of React, because you sued Facebook.
In situation B (React is licensed under just BSD), the patent rights necessary to use React are not written in explicit terms. You have made no explicit agreement to have your patent grant to use React revoked when you sue Facebook for patent infringement. In addition, without an explicit patent grant, a patent grant is implied with the license. You can at least continue to use React until the results of the court case.
> In situation A/C (React is licensed under BSD + PATENTS), you have explicitly agreed to have what is essentially your lawful use of React immediately revoked if you sue Facebook for patent infringement.
No you haven't. That is not what is written in the PATENTS file. The PATENTS gives you a patent grant to any react patent facebook may or may not have, that you can only lose if you sue facebook for patent infringement. Without the patents file, you don't have any grant to those patents.
> You have to immediately stop using React.
No you don't. Why do you think this is the case? There is nothing in the PATENTS file about this at all. All it says is that you lose the grant. If a court grants a preliminary injunction, then yes, you have to stop using it immediately, but guess what: assuming Facebook has some react patents, they can apply for a preliminary injunction against you whether or not the PATENTS file is in there. With just plain jane BSD they can also get a preliminary injunction.
> In addition, without an explicit patent grant, a patent grant is implied with the license.
It's totally misleading to state unsettled law as fact like this. It's wishful thinking. Not being a patent holder myself, I would like it to be true as much as anyone, but the fact is that until this stuff ends up in court, just assuming that a license to redistribute also implies a license to any patents is just a theory.
It's totally misleading for you to state unsettled law as fact like this. None of this has been tried in court so even what you have written carries a degree of speculation.
When Facebook explicitly includes a revocable patent grant (aka the PATENTS file), the argument of it being a "BSD license with no patent grant" when the patent grant is revoked is self-fulfilling. But if the PATENTS file had never existed, then what you have is a "BSD license with a debateably implicit patent grant", which has been the topic of debate long before React even existed, and has yet to be tried in court so could set a precedent, and is a way better bet for the consumer than a "BSD license with no patent grant because that patent grant has been explicitly granted and now revoked, no debate, period".
In situation B (React is licensed under just BSD), the patent rights necessary to use React are not written in explicit terms. You have made no explicit agreement to have your patent grant to use React revoked when you sue Facebook for patent infringement. In addition, without an explicit patent grant, a patent grant is implied with the license. You can at least continue to use React until the results of the court case.