The W3C Rule Interchange Format (RIF) Working Group has published six Last Call Working Drafts. Together, they allow systems using a variety of rule languages and rule-based technologies to interoperate with each other and with other Semantic Web technologies. Three of the drafts define XML formats with formal semantics for storing and transmitting rules:

• The RIF Production Rule Dialect (PRD) is designed for the kinds of rules used in modern Business Rule Management systems.
• The RIF Basic Logic Dialect (BLD) is a foundation for Logic Programming, classical logic, and related formalisms.
• The RIF Core Dialect is the common subset of PRD and BLD, useful when having a ubiquitous platform is paramount.

The other drafts:

• RIF Datatypes and Builtins (DTB) specifies the datatypes and standard operations (modeled on XPath Functions) available in all RIF dialects
• RIF RDF and OWL Compatibility specifies how RIF works with RDF, RDFS, OWL 1, and OWL 2.
• RIF Framework for Logic Dialects (FLD) provides a mechanism for specifying extended dialects, beyond BLD, when more expressive power is required.

The Working Group requests comments be sent to public-rif-comments@w3.org by 31 July 2009.