Here is the problem and the difference with the ERB type of copyright.
Edgar Rice Burroughs wrote books which he allowed the public to read and indeed resell when finished with them. He never allowed the public to use the characters created by him in those books or to use his words and intellectual copyright material in any other way, thus retaining full copyright control over his work and its derivative rights such as film and other and differing media usage from which he profited.

An artist at any of the market sites does much more than EHB. He or she provides the original material for legal reuse and commercial resale through other media, i.e. renderings etc..

From the Rendo licence:

"The Artist (Author) retains all copyrights to the enclosed materials. The Buyer is not purchasing the contents, only the right to use the contents. The Buyer may not redistribute this archive file, inwhole or in part. The Buyer may not store it any place on a network or on the Internet where it may be referenced by a third party. Buyer acquires the copyright to any derivative works created using this work, provided none of the original materials can be extracted from the derivative work by any means.
If Artist can show that any of the original material can be extracted from Buyer's derivative work, Artist can demand both the original and derivative work, and all copies thereof be deleted. For example, Buyer cannot make an image of a texture map mapped to a flat plane, such that the original texture map can be cut & pasted from the image. This is designed to protect the Artist from Buyers releasing work, which lets other users obtain the copyrighted material, and is not meant to infringe upon the artistic endeavours of the Buyer. Buyer may not make any MetaStream animation files with the enclosed materials, until this format can protect the original materials from being extracted. Items sold at Renderosity may not be used for illegal purposes."

So what does this mean.

1. If a games developer sees a great character here (think Laura Croft stuff) he can use a purchased Market character for any games product he wants to develop so long as the original meshes and textures can’t be extracted. Thus the artist (who still owns copyright) cannot earn a penny out of it. Indeed if the Games developer seriously enhances the product the Artists original copyright might no longer even apply to the new character. And the derivative rights such as film (based on the game plot and enhanced character) will probably belong to the games developer and not the original artist
2. A toy maker like Mattel can take a Marketplace character, pose it and do some poly subdivision on it and run it through a Cad-Cam Rapid prototyping machine and hey presto brand new Toy. Again since the original mesh and textures cannot be reverse-engineered from the toy, Mattel can legaly do this. Again with enhancement even the artist's original copyright may not apply. One of the chief toy-prototypers for Mattel used to post in the Rhino Forum here some years ago about the process, not that I am in any way suggesting that he would do this.
3. A clothing designer can do the same as the above, and a myriad of other idea-hungry manufacturers can do the same with any of the commercial products and most of the free ones.

And the above applies to the legal scrupulous manufacturers who would at least buy one copy of the product from the artist, Although with most products under $30 it is dirt cheap in terms of development costs.

But there seems to be a serious deficiency in the licensing on all of these products in that all of them can be legally used for the creation of a whole lot of products that are potentially very high earners with the original artist getting ZERO in royalties despite retaining copyright. Seems to me the thing is a bit of a mess.

And with the talents and product diversity of many of the manufacturers increasing, the attractiveness of such products to manufacturers with other plans for them is becoming obvious.

Regards
STORM