WordPress being a registered trademark, itâ€کs no wonder that the WordPress Foundation is concerned with its proper representation. On one hand, the Foundation wishes to make it easy for anyone to use the WordPress trademark for WordPress-related products and services, but, on another, they are keen to make it hard on anyone to profit off the trademark unfairly.
The general rule is that the use of the WordPress trademark requires permission from the WordPress foundation. Permission will be granted for use in a project:
But thatâ€کs not all: the trademark can be used without permission in order to refer to a product, project, or service, as referring or related to the WordPress open source project without claiming affiliation. This is what is probably of interest to most web developers: you can use the WordPress trademark even for commercial purposes if your business is somehow related specifically to WordPress: website design, theme design, plugin development, and the like. Therefore, we strongly encourage you to use terms such as â€œindependently developedâ€œ, â€œpowered byâ€œ, and â€œthird partyâ€œ when describing your product, project, or service.
There is an important exception: you cannot use WordPress as part of a domain name. WP, for instance, is completely allowed.
One final thing: itâ€کs WordPress, with capital W and capital P. If you are going to use the trademark, use it correctly.