In cases of fair use, members of the public may use or refer to a registered trademark without a license from the owner.
Examples of Fair Use
If you are a journalist interested in writing articles that include the term Linux, you do not need a sublicense. If you are printing up pencils, stenciling T-shirts, or distributing coffee cups with a legend on them like "Linux® is the greatest!" or "Even my Mother uses Linux®!" this is normally considered fair use.
Some uses of Linux require the user to obtain a sublicense.
Examples of Use Requiring A Sublicense
If you plan to market a Linux-based product or service to the public using a trademark that includes the element "Linux," such as "Super Dooper Linux" or "Real Time Linux Consultants" you are required to apply for and obtain a sublicense from the Linux Foundation. This is true whether or not you apply to register your trademark with a government.
If in Doubt, Find Out
Many questions are answered in the FAQ. If you are unable to locate an answer to your question, please contact us at firstname.lastname@example.org.