Compliance, in DRM, references a manufacturers’ adherence to output copy protection. Manufacturers who distribute digital rights management (DRM) equipment must comply with copy protection rules, which include protective measures. These protective measures and technologies prevent hackers from copying unauthorised materials. Technical documents are specified within private license contracts, which apply to the equipment implementing DRM. In conjunction with compliance rules, manufacturers must adhere to robustness rules further protecting against hackers attempting unrestricted copying. Usually they are private in nature, while others are public. Compliance rules pertaining to DRM devices also pertain to software and are similar to behavioral rules. Adherence to them should be in conjunction with robustness rules, each under the umbrella of DRM laws and regulations.