I have seen a few logos listed on Wikimedia Commons with the text: " This image only consists of simple geometric shapes and/or text. It does not meet the threshold of originality needed for copyright protection, and is therefore in the public domain. Although it is free of copyright restrictions, this image may still be subject to other restrictions." Now I know that this surely doesn't apply to all logos. How do you then differentiate between a logo that is copyrighted and one that isn't? I've seen a logo that has TM, which means its a registered trademark - so surely you can't use that.