Out of curiosity, how often do violations of open source software licenses result in enforcement (e.g. court case)? Even then, it seems the worse case is a requirement retroactively adhere to the license — monetary penalties seem like they wouldn’t apply to something being given away at no charge anyway, right?

As a independent open source author, if big corp doesn’t abide by my license, am I really going to pay lawyers from my modest savings to sue them so that they abide by my license? Seems there’s a practical asymmetry that makes open source licensing largely theoretical for all but a handful of the biggest projects out there. Of course, I’d very much like to be proven wrong.