I`m not sure that art.com has the ability to do this, as it seems that they are a retailer and not a brokerage for licenses and royalties. Chances are the individual artists have granted art.com certain licenses, but that doesn`t mean they can negotiate on the artist`s behalf.
Finding any contact information on some of these artists seems difficult, so you might be able to get their contact information through contacting art.com, depending on the arrangement the artist and art.com have with each other.
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