body: `The Linux Foundation` is a registered trademark of The Linux Foundation.
  
  
  `Linux` is a registered trademark of Linus Torvalds.
  
  
  But `Linux` is a substring of `The Linux Foundation`.
  
  
  Is it OK for someone to claim a trademark including another trademark as a substring (such as `The Linux`, `My Linux`, `Free Linux`, etc.)?
  
  
  
title: Substrings used in a trademark