You make a lot of good points, but I want to focus on just one.

> This license will not have the effect of stopping patent litigation. Patent trolls don't use React, and most of the danger is still trolls.

I agree. However - implicit in your position (and my apologies if I am reading you wrong) is that there are small players - or any players - who have valid software patents that should be exercised against anyone - much less Facebook. As a general proposition, I'm hesitant to support that.

Let's put it another way - but first get some caveats out of the way: there may be things problematic with this license (your points are highly illustrative - especially about the systematic, higher-order effects). I also think that, as someone in private practice, I'm empathetic to Facebook's attorneys' goals here, and they are likely saving Facebook a whole host of headaches. I am also very well aware of the counterbalancing arguments regarding the duty of good stewardship of the open source community, and decisions like this by gigantic players such as Facebook have lasting effects for the entire community. /caveats

However - defense of the right to pursue infringement litigation over software patents against anyone is simply not a hill I am willing to die on. I am struck, as a result, by confusion at the willingness of open source lawyers to criticize facebook for license limitations aimed at limiting the rights of licensees to initiate patent suits - even if it is a self-serving limitation. My instinct is that, in general, push-back against limitation (even imperfect ones) of the exercise of software patent rights, within the open source community, should be a fairly low priority. I'm happy to stand corrected - it happens often enough.

Let me make a crude analogy - if you believe in certain forms of gun control, this would be the equivalent of a debate about what type of assault weapons may be owned by the public. If you are of the view that no assault weapons (and I am using the term very, very broadly - I'm not interested in the highly technical debates of what constitutes an assault weapon for these purposes) should be owned by the general public, then law banning the ownership of a particular type of assault weapon against by a particular class of owner is not that big of a deal - even if it is crudely implemented. If anything, it may be a step in the right direction. Accordingly, the criticisms of the BSD+Patent license by the open source community strikes me as analogous to criticism of a partial assault weapons ban by gun control advocates - it is a bit of a head-scratcher.

Back to this license, in more concrete terms - I am skeptical of the claim that there exists an entire class of small companies have that meaningful software patent portfolios that can be exercised against facebook, much less anyone, which companies will be disenfranchised of their rights by this license:

* First, software patents are severely diminished in the post-Alice world, as a category, and very likely to be invalidated in an enforcement action, especially against a company as wealthy and sophisticated as Facebook. Patent litigation with Facebook is going to be as scorched-earth as it can get - the arrow of the BSD+Patents license is but one in a quiver that is full of millions in cash and tens of thousands of associate hours.

* Second, if you have the wherewithal to enforce a patent, you have millions of dollars in attorneys fees at your disposal - meaning you are not very small. Patent infringement litigation is called the sport of kings for a reason - it is monstrously expensive (I seem to recall statistics stating that a 'simple' patent claim is on the order of $1.5-3M to litigate to conclusion, per party).

* Third, if you have non-software patents (e.g., medical devices, drugs, chemical compositions, manufacture processes, semi-conductors, etc.) - it strikes me that there is a low (maybe not zero, but low) chance that facebook's BSD+Patents license constitutes a substantial portion of your 'critical' software stack.

* And, finally, if after all this, you are a small startup without a lot of money and you are trying to enforce software patents against Facebook (of all possible litigants, I can think of no larger juggernaut), and react (or any other BSD+Patents licensed software) is a part of your critical stack - there are so many other existential questions about the company's strategy that the particular terms of this license are rather low on the list.

As I said, I am very happy to hear any feedback, and thanks for your thoughtful responses.

Edit / update:

A few notes, in no particular order:

Tl;dr - two main cases here: 1. one is trying to enforce software patents against facebook - I am not going to spend a lot of energy defending the exercise of software patents, generally; 2. one is trying to enforce non-software patents against facebook - I believe there is a low chance that Facebook's BSD+Patents software constitutes a meaningful part of your stack in this instance.

* You are likely viewing this issue from the point of view of someone who chooses what sorts of licenses Google should adopt. I very much appreciate your insight and criticisms from that perspective. However, I am viewing it as counsel to a lot of small companies that have to be nimble - accordingly the scenario in question, where this license is a limitation of a startup's ability to succeed, involves that startup having been misguided into thinking that it is a good idea to sue Facebook for patent infringement over a software patent while also relying on Facebook software as a part of their critical stack. That is... quite a scenario. It reminds me of this scene from Dark Knight:

Lucius Fox: [in his office] Let me get this straight. You think that your client, one of the wealthiest, most powerful men in the world, is secretly a vigilante who spends his nights beating criminals to a pulp with his bare hands; and your plan, is to blackmail this person?

[pause, Reese looks nervous]

Lucius Fox: Good luck.