Since I'm keen to release a fabric line based on my growing library of reproduction vintage fabrics, I've researched pretty heavily into the copyright restrictions that might apply. As it turns out, it's common practice for big-name designers to recreate vintage fabrics and graphics - here are some of the examples I've come across...
Perhaps the most famous example is Amy Butler's Chrysanthemum print; blogger Dorie came across a vintage tablecloth at a garage sale, in what was clearly the source fabric.
Michael Miller fabrics also create not just retro, but repro. I can't find where I originally saw this one (I saved the images out of interest during the course of my research), but on the top is an original 1950s barkcloth, and on the bottom "Bobby Sock Rock" by Nicole for Michael Miller.
Lastly, I love this design from the "Fifi & Fido" collection by Anna Griffin, but it was just today while browsing on Vixen Vintage that I spotted the inspiration, this "Kitten-ettes" shoebox.
I turned up another from Anna Griffin while I was searching for a picture of the cat fabric - I noticed this dress form fabric was a perfect replica of a vintage feedsack fabric I'd saved in my 'to repro' file! Guess I'm saved a job. I prefer the original colourway though (on the left).
And these are just the ones that can be matched with their inspiration - I'm sure there are many, many more. Now, obviously I'm totally down with reproducing vintage fabrics; the only thing that slightly bugs me is that none of these openly acknowledge the copying - at least not until it's uncovered. But why make it a secret? I actually love knowing that the retro-looking print I'm admiring is based on graphics from a 1955 shoebox or a 1940 magazine!