FWIR from a really old thread, the ESA’s Guppy was said to be a ripoff of a Boeing design.
“......ripoff of a Boeing design.”
Take some time, and read at the following site:
http://www.allaboutguppys.com/sg/377sgf.htm
I suppose I found it fun to read the article, because I used to watch these things take off, and land when I was a kid working on the Long Beach Airport. Lots of memories.