What is a rogue anti-spyware program?

Typically, a rogue spyware program is one that claims to be able to detect and delete spyware although is inadequate at doing so. This may simply be because it's definition files (usually shortened to defs) are not updated often enough. More suspicious ones may actually contain spyware themselves, sometimes attempting to persuade the user that buying the rogue product will completely eradicate all spyware threats. Probably the most-updated and accurate site listing rogue anti-spyware programs is Spyware Warrior's rogue list.