When people talk about lowercase-f &quot;free&quot;, they often aren&#x27;t talking about copyleft- in my experience lowercase-f &quot;free&quot; is ambiguous to a lot of people. People who know nothing about open source software might assume free-as-in-price. Even people who know quite a bit about open source licensing might use lowercase-f &quot;free&quot; to refer to open source licenses in general, despite RMS and the FSF attempting to own that word in Orwellian fashion.<p>That&#x27;s a long way of saying, I disagree with your definition of copyleft as simply requiring you to keep your modifications free- rather, the definition of copyleft simply requires you to keep your modifications also copylefted. I&#x27;m sure you know that as well, I&#x27;m not nitpicking you so much as using your comment as a starting point for a tangential rant. :)<p>Of course, if you buy into the FSF&#x27;s attempt to co-opt the word &quot;free&quot; to only refer to their brand of freedom, what you said makes sense, but their habit of trying to co-opt common, ambiguous words like &quot;freedom&quot; to mean something very, very, very specific that they define is probably one of the top 2-3 reasons why they&#x27;ve driven so many people away from their cause over the past few decades. If they mean copyleft, they should just say copyleft. Trying to co-opt &quot;free&quot; is at best either dishonest marketing (because who hates freedom, right?) or a dishonest rhetorical device. It&#x27;s used as a passive aggressive way of laying claim to a word that means lots of different things to lots of different people, even within the context of open source licensing. To the FSF&#x27;s detriment, it confuses every single discussion about their goals, because it&#x27;s never clear whether someone means free-as-in-beer vs. free-as-in-freedom vs. free-as-in-RMS.<p>And let&#x27;s be clear- free-as-in-freedom is a different thing from free-as-in-RMS. Free-as-in-RMS can be a great thing too, I just wish they would be more intellectually honest about it.