The lawsuit, filed Monday (12/18) in San Francisco, seeks to stop Sagan from selling these materials in what the lawsuit claims is a violation of federal and state laws.

Sagan acquired the memorabilia when he purchased some of the late concert promoter Bill Graham's assets from Clear Channel Entertainment, which had purchased Graham's company following its founder's death. Graham's legendary archives included concert posters, T-shirts and other items which the lawsuit claims were never authorized for sale.

"Sagan simply doesn't have the legal rights to exploit and profit from the extraordinary success of these musicians," said attorney Jeff Reeves, who represents the musicians in a press release. "This memorabilia was created in the first place for the purposes of promoting concerts and as gifts for fans and concert crew. Graham himself did not have the right to sell, reproduce or otherwise exploit these materials as a promoter, and neither does Sagan, who was not authorized to purchase these materials and who has absolutely no connection to the artists or their music."

"We have never given permission for our images and material to be used in this way," The Grateful Dead [ tickets ]'s Bob Weir said in the press statement. "What Sagan is doing is stealing. He is stealing what is most important to us--our work, our images and our music--and is profiting from the good will of our fans."

Sagan bid the winning amount--$3.8 million--in an October bankruptcy auction to acquire Tower.com, the web address of West Sacramento, CA-based Tower Records, which filed bankruptcy this year and is going out of business in the US.

The deal Tower.com deal is currently in limbo after Tower filed court papers later in October, claiming Sagan was trying to back out of the deal or renegotiate the terms.