Comment by carussell

The MIT License arguably protects against patent litigation (in contrast to BSD).

People who have an issue with the MIT License (on the patent issue) fall into one of two categories:

a) People who've put it in the same category with BSD in their heads at some point, associating with it the same shared caveat about patents, and

b) People who understand the distinction between the two but are unsatisfied with how terse it is (especially in contrast to e.g., Apache 2.0). This isn't helped by the fact that the MIT License doesn't actually use the word "patent", and the closest it gets to saying "irrevocable" is "without restriction"/"without limitation".

In any case, Microsoft also included a custom patent grant at the time they announced the CLR's availability on GitHub and its new, more agreeable license terms. (Unfortunately it doesn't include the word "irrevocable", either.)