This chapter considers the theme of trespass in cyberspace. In order to prevent unauthorized use of their data several U.S. companies have hastily filed lawsuits alleging trespass to chattels. But some of this data usage, especially for metasites, is socially valuable. Nonetheless, the courts are generally sympathetic with these trespass claims even if this means that activities like spidering or e-mail are constrained in certain contexts. Legal scholars have criticized this trend because it creates a novel property right in factual data which is not eligible for copyright protection. These legal concerns are justified, but what should moralists be saying about this matter? We argue here that both eastern and western philosophies recognize the need to respect the common good of a community or common venture. This awareness should temper a company’s narrow focus on proprietary property rights. We attempt to define the Net’s common good (or commonly shared values) and make the case that Internet users have a prima facie duty to support that common good. Thus, prudent and morally responsible companies operating on the Net will seek to balance their property entitlements with this affirmative duty to support the Internet’s common good. There is no magic formula for achieving this precarious balance, but we offer some general criteria that will orient managers toward the right direction. Finally, we explain that a private settlement of trespass matters is clearly welfare-enhancing.