The guitar company said in a released statement that it took "this action reluctantly, but is required to protect its intellectual property." Earlier this month, Activision filed suit in California asking a federal judge to declare the game does not violate the patent.

Spokeswomen for Wal-Mart and Amazon.com said the companies do not comment on pending litigation. Officials with the four other retailers did not immediately return calls seeking comment. Santa Monica, Calif.,-based Activision contends Gibson's patent assertions have no merit. Gibson has said it wants Activision to stop selling "Guitar Hero" until it gets a license under the patent.

"Our 'Guitar Hero' retailing partners have done nothing wrong," Activision said in released statement. "We will confront this and any other efforts by Gibson to wrongfully interfere with Activision's relationship with its customers and its consumers."

Gibson attorneys sent Activision a letter in January accusing it of violating a patent titled "System and Method for Generating and Controlling a Simulated Musical Concert Experience," according to a lawsuit filed by Activision.

A copy of the patent is included in Gibson's lawsuit and dated Nov. 23, 1999. It describes a device that lets a user "simulate participation in a concert by playing a musical instrument and wearing a head-mounted 3-D display that includes stereo speakers." The device also includes playback of audio and video of a prerecorded concert and a separate track of audio from the user's instrument.

"Guitar Hero" users perform songs using a stringless, plastic guitar that plugs into a game console. A TV connected to the gaming console displays animated musicians playing along and graphics that guide users' play.
In Gibson's lawsuit, it states the company "has been damaged and will continue to be damaged by the aforesaid infringement unless defendants are enjoined, preliminarily and permanently, from selling and offering for sale infringing products ..."

Founded in 1894 in Kalamazoo, Mich., and headquartered in Nashville since 1984, Gibson Guitar Corp. has brands including Dobro, Maestro, Kramer, Steinberger, Tobias, Echoplex and Wurlitzer. The various "Guitar Hero" titles have helped boost Activision's sales, with the company reporting last month a 90 percent increase in profit for the third quarter ended Dec. 31 - in part due to strong sales of "Guitar Hero III: Legends of Rock."