The Office of Management and Budget, in the Executive Office of the President, in a May 9, 2013 memo (OMB-M-13-13, Open Data Policy-Managing Information as an Asset), defines Open Data this way:
Open data: For the purposes of this Memorandum, the term "open data" refers to publicly available data structured in a way that enables the data to be fully discoverable and usable by end users. In general, open data will be consistent with the following principles:
• Public. Consistent with OMB's Open Government Directive, agencies must adopt a presumption in favor of openness to the extent pennitted by law and subject to privacy, confidentiality, security, or other valid restrictions.
• Accessible. Open data are made available in convenient, modifiable, and open fonnats that can be retrieved, downloaded, indexed, and searched. Formats should be machine-readable (i.e., data are reasonably structured to allow automated processing). Open data structures do not discriminate against any person or group of persons and should be made available to the widest range of users for the widest range of purposes, often by providing the data in multiple formats for consumption. To the extent permitted by law, these formats should be non-proprietary, publicly available, and no restrictions should be placed upon their use.
•Described. Open data are described fully so that consumers of the data have sufficient information to understand their strengths, weaknesses, analytical limitations, security requirements, as well as how to process them. This involves the use of robust, granular metadata (i.e., fields or elements that describe data), thorough documentation of data elements, data dictionaries, and, if applicable, additional descriptions of the purpose of the collection, the population of interest, the characteristics of the sample, and the method of data collection.
•Reusable. Open data are made available under an open license that places no restrictions on their use.
•Complete. Open data are published in primary forms (i.e., as collected at the source), with the finest possible level of granularity that is practicable and permitted by law and other requirements. Derived or aggregate open data should also be published but must reference the primary data.
•Timely. Open data are made available as quickly as necessary to preserve the value of the data. Frequency of release should account for key audiences and downstream needs.
•Managed Post-Release. A point of contact must be designated to assist with data use and to respond to complaints about adherence to these open data requirements.