There is when you're actively sabotaging the other company trying to use the open source thing you wrote.

Which is what's happening here: Wordpress started out with blocking WPEngine's access to plugins on wordpress.org, which fine, Matt runs it so he can do so. But that's clearly a conflict of interests that he has the unilateral ability to block anyone's access because of a business dispute.

Then he moved on to adding a checkbox that requires you to swear you're not related to WPengine in any way to access wordpress.org as well as banning people that asked any questions on the developer slack, which again, is fine, but it's clearly indicating that Matt has some conflicts he's unwilling to resolve.

Then he forked the most popular wordpress plugin (which is the property of WPEngine) which again, is fine. What WASN'T fine is he redirected the ACF url on wordpress.org to his fork. That's, again, a clear sign he's conflicted as hell and taking actions that are utterly absolutely unaccptable.

If he had just made it a 404, or whatever, then cool. But to just silently give you a different piece of software? He can fuck off with that nonsense.

That's the problem here: he's doing lame-brained nonsense because he believes the opensource side and the business side are both his (because he's structured it so they are) and is actively, and aggressively, doing shit to screw with people he doesn't like because they're a threat to his business.

Not remotely acceptable, and he needs to be slapped down so hard he ends up being six inches shorter.