I have a few coins that I love and made some T-shirts with their logos and my down design incorporated with them. I showed some people and they are interested in buy. Are logos copyrighted or are they public domain? Can I open a shop with products having alt-coin logos on them? or would I need to contact each developer team?
You’ll have to research every single logo before using them. However, I think that the Bitcoin logo is not copyrighted. I AM not sure, though. I doubt that any of the big coins’ logos are copyrighted.