Version 2.1 of ContentGuard's Extensible Rights Markup Language has been submitted to the OASIS Rights Language Technical Committee, and will serve as "the basis in defining the industry standard rights language" outlined in the TC's charter. The Rights Markup Language TC has been established by ContentGuard, Microsoft, and other OASIS members to "define the industry standard for a rights language that supports a wide variety of business models and has an architecture that provides the flexibility to address the needs of the diverse communities that have recognized the need for a rights language." The XrML 2.1 release contains two main parts, in addition to four XML schemas: (1) Extensible Rights Markup Language (XrML) Core 2.1 Specification defines the core of XrML, "a general-purpose language in XML used to describe the rights and conditions for using resources. It explains the basic concepts for issuing rights in a machine-readable language and describes the language syntax and semantics; the goal is a language that can be used throughout industry to stipulate rights to use resources and the conditions under which those rights may be exercised and by whom." (2) Extensible Rights Markup Language (XrML) Standard Extension 2.1 Specification builds upon XrML Core 2.1 by defining "a set of concepts that are generally and broadly useful and applicable to XrML2 usage scenarios, but which are not necessarily at the heart of XrML2 semantics; these concepts are broadly classified, according to the purpose that they serve, into conditions, payment notions, properties, and revocation extensions."

From the XrML Core 2.1 Specification:

This document explains the basic concepts for issuing rights in a machine-readable language and describes the language syntax and semantics. It does not provide specifications for security in trusted systems, propose specific applications, or describe the details of the accounting systems required. One of the goals of this document is to develop an approach and language that can be used throughout industry to stipulate rights to use resources and the conditions under which those rights may be exercised and by whom. This document does not address the agreements, coordination or institutional challenges involved in achieving that goal.

Schema Conventions: The syntax of XrML2 is described and defined using the XML Schema technology defined by the Worldwide Web Consortium (W3C). Significantly more powerful and expressive than DTD technology, the extensive use of XML Schema in XrML2 allows for significant richness and flexibility in its expressiveness and extensibility. To that end, a principal design goal for XrML2 is to allow for and support a significant amount of extensibility and customizability without the need to make actual changes to the XrML2 core itself. Indeed, the core itself makes use of this extensibility internally. Others parties may, if they wish, define their own extensions to XrML2. This is accomplished using existing, standard XML Schema and XML Namespace mechanisms.

At the heart of XrML2 is the XrML2 Core Schema. The elements and types defined therein define the core structural and validation semantics that comprise the essence of the specification. It is expected that every XrML2 validation processor will be aware of the semantics embodied in this core... The single most important concept in XrML2 is that of the License. A License is conceptually a container of Grants, each one of which conveys to a particular Principal the sanction to exercise some identified Right against some identified Resource, possibly subject to the need for some Condition to be first fulfilled. A License is also a container of GrantGroups, each of which is in turn an eventual container of Grants..."