In reply to Marc Perel.

Thanks Marc for responding and to Matt for bringing up another good example, I'm glad I'm not the only one who caught it.

While the licensing page does a good job explaining the GPL and the freedoms it allows, there are a couple of things that are suspect.

You can fork Layers, create a modified derivative (it must be 20% unique)

Who says the code has to be 20% unique for it to be a derivative? What makes a product derivative is subjective to everyone as there hasn't been a court case that proves otherwise.

Layers may be included on a WordPress Multisite implementation where you charge for themes or a service built on Layers. However, it must be under the terms of the GPL license. Therefore, you must make the source code available to the users of the program as described in the GPL, and they must be allowed to redistribute and modify it as described in the GPL.

If I take Layers which is GPL Licensed and make it a part of a service offering to customers without any distribution occurring, then the GPL doesn't apply. The GPL is only transferred to customers if distribution occurs.

Layers Pro has special licensing that governs resale, access to updates and support. If you plan to resell Layers Pro as part of a platform, service or theme/extension, you must acquire a developer license to do so. This license grants you the necessary copyright transfers to support the redistribution rules put forth by the GPL.

This sounds to me like you're saying Layers Pro is GPL licensed but I can't resell it unless I purchase a developer license. The GPL doesn't say I need to purchase a developer license to resell someone's code. The redistribution rules of the GPL don't require money to be transferred.

When it comes to the GPL license, less is more.

I'm not a lawyer, I'm not even a license expert but I have written about the GPL License extensively over the years and some of the wording in this document is on the borderline of being restrictive or at the very least, inaccurate.