Originally posted by DJeX
microsoft does it
Microsoft AntiSpyware? No, they just bought a company that makes antisyware software. But it comes with their own definitions.
Anyway, look around at sites like download.com, find a nice list of antispyware programs. Look on their sites and see if you can download the definitions. Your next problem is probably figuring out how the definitions should be used, i don't think there is any company out there that will tell their users how to use their definitions in your own software unless you make a partnership with them and pay loads of money.