Reprinted with permission from

The ancient legal doctrine of trespass to chattels establishes liability when one person dispossesses or causes physical harm to the chattel (private property) of another person.

What does that doctrine have to do with conduct in cyberspace? Quite a lot, actually.

Information technology development continues to advance at an astonishing pace, and with the law evolving at a much slower rate, traditional legal theories have had to be dusted off to grapple with Internet disputes. The best example is the application by the courts of the trespass to chattels notion to the new world of the Internet.

Some of the first Internet trespass cases involved unsolicited commercial e-mail (aka spam). For example, in the Compuserve v. Cyber Promotions case, the court sustained an Internet service provider's claims of trespass against a spammer who sent bulk e-mail spam to the ISP's members.

It seems that the trespass to chattels legal theory is alive and well in cyberspace.

Other courts have found spam generators liable for trespass to chattels when they sent spam through another's computer facility. A case in point is AOL v. LCGM, in which the defendant transmitted more than 92 million e-mail messages to AOL members while advertising pornographic Web sites, and which resulted in 450,000 complaints to AOL. The court held that the e-mail practices constituted trespass to chattels.

And in AOL v. IMS, the defendants sent 60 million messages to AOL members, many of which contained as a falsified return address in the header. The court held that the defendant's unauthorized contact with AOL's computer network amounted to trespass to chattels.

More recently, with spam messages finding their way onto cell phones, Verizon Wireless has filed suit against various cell phone spammers, asserting various causes of action, including trespass to chattels.

Furthermore, in Kerrins v. Intermix Media, a court held that trespass is a viable legal theory to address alleged distribution of spyware and adware programs.

It appears that the model behind these decisions is that the Internet is like a series of private stores, where Web sites can determine under what circumstances people can gain access and use information. This point is best brought home by the case of eBay v. Bidder's Edge.

In that case, Bidder's Edge, by using a Web-crawling program, or "spider," compiled listings for specific items from various online auctions, including eBay, and placed them on the Bidder's Edge site. eBay asserted that this practice trespassed its servers. Bidder's Edge argued that it merely was providing a service by compiling information from the public domain.

The judge granted a preliminary injunction in favor of eBay on the basis that Bidder's Edge's spider, along with potential spiders of other companies, if allowed, could slow down eBay's servers. The judge noted that "eBay's servers are private property, conditional access to which eBay grants the public." This, obviously, represents the private store model of the Internet.

However, there are some courts that instead have adopted a public library view of the Internet, where people can access Web sites and information as they deem fit.

This was true with respect to the case of Ticketmaster v. There,, by deep linking, had made Ticketmaster tickets directly available on the site while bypassing the gateway advertising pages on the Ticketmaster site.

Ticketmaster raised the trespass theory, but it failed on a preliminary injunction motion. The judge found that the Web crawlers used by to temporarily copy information from the Ticketmaster site did not come within the ambit of what the trespass laws were designed to redress.

Also, the trespass theory did not succeed factually in the case of Intel v. Hamidi. In that case, a former employee sent six waves of thousands of e-mails to Intel employees over a two-year period complaining about Intel's personnel practices. The California Supreme Court ruled in favor of the former employee and against Intel, because Intel had not proven damage to its computers or their usefulness. Perhaps this decision then embraces the public library model of the Internet when it comes simply to accessing and using information on the Internet.

Still, in the main, it seems that the trespass to chattels legal theory is alive and well in cyberspace, especially when aggrieved parties can show actual harm or interference with their computer systems.

Does this matter? Yes, indeed. There need to be mechanisms to resolve disputes, even, and perhaps especially, in new contexts.

Eric J. Sinrod is a partner in the San Francisco office of Duane Morris. His focus includes information technology and intellectual-property disputes. To receive his weekly columns, send an e-mail to with "Subscribe" in the subject line. The views expressed in this column do not necessarily reflect those of Sinrod's law firm or its individual partners.

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