Since 1978 an Artist's work no longer has to be registered or even bear a symbol to have some level of copyright protection. We cannot offer you advice regarding artwork incorporated into commercially sold crafts. However, manufacturer names are listed on our product pages so that you may do your own research on allowable use.
Paper Products Design (PPD) based in California provides paper napkins from individual artists with whom they have strict licensing agreements. Please bear in mind their copyrights policy, when working with these unique napkins for decoupage crafting. Consult their website for more information.