The re3data.org schema is a list of metadata properties describing a research data repository regarding its general scope, content and infrastructure as well as its compliance with technical, metadata and quality standards. The schema includes required metadata properties and optional properties providing additional information. The schema is designed to recommend a standard for describing a research data repository; provide the basis for interoperability between research data repositories and re3data.org; be one of the first steps towards the goal of a certificate for research data repositories. This is the RFC Version 2.2 of the schema that we invite you to comment on. We highly appreciate your feedback that will be discussed and integrated in the final version 2.2 of the schema in December 2014.