Having a proper definition that sets a border between useful tools and malicious software is crucial, according to Ari Schwartz, associate director of the Center for Democracy and Technology.
"The anti-spyware community needs a way quickly and decisively to categorise new programs. The definitions will serve as a foundation for all future efforts to help users make more informed decisions about which programs to keep and which to delete."
Many of the ASC's members publish spyware filtering and removal tools. Future versions are expected to use the newly agreed definitions to determine which applications should be labelled as malicious.
The ASC defines spyware as software that impairs the users' experience, operates outside their control and collects personal data without their consent. A PDF of the full definition can be downloaded here.
The public is invited to comment on the draft definition until 12 August, when the group will create a final version.
A clear definition of spyware could end disagreements about the usefulness or otherwise of certain software tools, as many vendors take offence at the spyware label.
Gator, for instance, has been very vocal in describing its software tool as beneficial to users, and has been variously included and removed from many spyware removal tools in recent months.
Critics, however, warn that any definition of spyware will be used by makers of malicious tools to evade detection and removal by anti-spyware applications. They could use the guidelines to tweak their software to ensure that it fall outside the definition.
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