Sort of in the line of thought of @DRE 's question on: https://xenforo.com/community/threads/how-do-you-copyright-a-style.25975/ I've seen many addons that have built-in branding, and then sell tokens or licenses that remove the branding. Some of these addons also ensure that if the branding is manually removed by the user without the appropriate tokens, the addon no longer functions. I was wondering if any of you might be familiar with the methods that would be undertaken to accomplish something like this. I'm working on an addon that, ideally, will have a small 'Add-on by Talaysen' down at the bottom, and I'll offer the plug-in for free, and then optionally sell a license (or some sort of validation token) that removes this attribution. (I'm not necessarily looking to profit off this addon, but the amount of work that's gone into it, I'd like to get credit where credit is due, or contribution otherwise ) Worth noting: I'd like there to be some kind of.. lack of functionality if the attribution is removed manually, without the validation token. I've been searching around on the forums, and on google, and haven't found anything quite on par with what I'm looking for. The closest thing I've found is the WHMCS licensing addon, it seems with that code, you could add this functionality to just about anything. Just curious what kind of methods other developers here use, or if anyone has any recommendations.