"Well, if you read the file you'd see that it's a grant of rights to use this software regardless of any patents Facebook has that may apply to said software.

It looks to be more or less the same as the relevant clause in the Apache 2.0 license that says "you can use our patents but if you sue us your right to use this software is automatically revoked." "

It 100% is not the same as Apache.

1. If you challenge any facebook patent's validity, at all, you lose the right to use the software. Apache has no such clause. (This is the "(b) that any right in any patent claim of Facebook is invalid or unenforceable.")

2. Apache is a tit for tat clause (for lack of a better term). If you have apache licensed software X, and sue someone about patents in X, you lose any granted patent rights to X. You keep rights to other software.

In Facebook's wording, if you have facebook software X, and sue Facebook about software Y, you lose granted patent rights to X.

The breadth is not the problem though. I'm perfectly fine with folks trying to prevent others from suing them.

However, this broad clause also applies to counter claims.

So if facebook sues you, and you counter claim, at all, you lose patents rights to all facebook software.

I actually know they have their good reasons to want to do this, but it is not a simple "you should feel good about this" type of situation.

I was merely trying to point out that contrary to what the OP seemed to be suggesting, this file is not a list of patents that Facebook says apply to this code, or anything else particularly nefarious.

Also, your paraphrasing leaves out the crucial bit that you only lose your rights if you sue Facebook for patent infringment. If, say, you decide to sue Facebook because you're sick of seeing the stupid Buzzfeed articles your so-called friends keep liking in your news feed, you can continue using their software.

...and the Apache 2.0 license belongs to a short list of licenses that have been extensively reviewed and can be trusted.

Every time someone comes up with a new license, the review work must be redone to ensure it respects the philosophy of Open Source. Which is why I prefer project published under well-known licenses (GPL2/3, LGPL, Apache, Mozilla, BSD, ...).

The package in question is licensed under BSD 3-clause license. I'm guessing the patent file is included as well to cover their bases.

BSD is generally viewed to have an implied patent license. The patent file is usually there to give you a different set of rights than you would have gotten, be it good or bad (and i've seen both :P)