React - MIT license

What’s all this stuff I hear about Facebook PATENTS clause?

“After studying the patent grant that covers React.js, I see it is not a problem after all. That program is ok to list”. Dr Richard Stallman - No problem with react.js

According to Sieminski, “The companies with the greatest concern are those that have large patent portfolios and engage in offensive patent litigation, especially against Facebook.”

Meanwhile, in private business, there is little controversy about using code under the BSD+patent terms. Most companies have examined the marginal legal risk of this license compared to others (like Apache 2.0) and considered it underwhelming. Unless a company decides to sue Facebook (or accuse its products), the termination trigger has no actual effect.

Where can I find answers to common questions about the additional patent grant?