How O is the LOD cloud? (revisited)

This post updates the analysis of the licensing practices in the datasets in the LOD cloud. Different snapshots of this reality were taken in 2009, in 2012 and 2013, which I summarized in a previous post. This is the LOD cloud diagram coloured by type of license:


RDFLicense: a dataset of licenses in RDF

RDFLicense is a dataset of 126 licenses (suitable for general works, data, etc.) expressed as RDF. The official URI of the dataset is:

While the dataset is also accesible at datahub:



According to, TBX (TermBase eXchange) is a system for the exchange of terminological data. It is an ISO standard (number 30042) and an industry standard (formerly from LISA; now from ETSI). It includes a family of XML markup languages (called TMLs, for Terminological Markup Languages; also called TBX dialects).


Why you should license your ontology

I have been asked this question and I am pleased to give my answer here.
Not the least of the reasons, is the AMOR manifesto highlighting this need.


An ODRL2.0 RDF editor

Tools need to be developed for new specifications if these are to be adopted.

Valid as a proof of concept and even useful for editing simple expression, a Simple ODRL Editor has been released at OEG (Universidad Politécnica de Madrid).

The tool is based on a Simple ODRL API, still under development...

The Simple ODRL Editor permits creating rights expressions,


Media Contract Ontology

The Media Contract Ontology is an ontology for representing contracts dealing with exploitation rights of audiovisual works. The ontology is a standard approved in 2013 --with already one ammendment-- and its specification is a document for which you have to pay.

Yet, for an informal description, we forward you to an informal description, divided in two namespaces:


OWL Validator

The whole point of Software Engineering revolves around the idea of building on existing work.
This is not the case for the Semantic Web, where semantic-applications applications appear and disappear like shooting stars. You have to invent the wheel, too ofen.
This is why I had to program myself a simple OWL validator, understood as follows:

An OWL Validator: is a service that determines whether an ontology is conformant with the different OWL profiles (OWL 2 EL, OWL2 QL, OWL2 RL).


Trying Fuseki

Fuseki is a SPARQL server. It provides REST-style SPARQL HTTP Update, SPARQL Query, and SPARQL Update using the SPARQL protocol over HTTP. It can be downloaded here.
Please to mind that Fuseki does not provide any security mechanism, so you will have to implement your own --like restricting the service to localhost etc.

Starting Fuseki with a loaded dataset in memory accepting UPDATE queries is as simple as:


ODRL 2.0

The Open Digital Rights Language (ODRL) Ontology has been released as a Draft!

Check it out and provide comments!


How to license content stylishly

If you have to license something, I bet it is because you own the intellectual property rights of a certain content (image, video, text...), you want to publish it (most likely in the Internet) and you do care about your rights. If so, this post is for you.

I also bet there is a link in a webpage pointing to the resource. In such a case you should.




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