author added "must be used for good, not evil" to the license
...and IBM asked for an exception.
https://en.wikipedia.org/wiki/JSLint#License
https://news.ycombinator.com/item?id=5138866
note that restricting use of software makes it non-free gpl-wise.
RMS said the GPL does not restrict rights of the USER of software, just that when the software is redistributed, the rights are passed along.