Macrovision is a company that licenses copy-control technology designed to stop analog copying of video. This technology has been included in DVDs, where it is intended to stop you from being able to make analog copies of your DVDs using your VCR. Macrovision has filed a lawsuit against 321 Studios, the leading vendor of DVD back-up software, arguing that 321 Studios' software violates Macrovision's patents for its analog copy protection technology and violates the anti-circumvention provisions of the Digital Millennium Copyright Act (DMCA).
