The PROTON Ontology is a basic upper-level ontology that contains about 300 classes and 100 properties, providing coverage of the general concepts necessary for a wide range of tasks, including semantic annotation, indexing, and retrieval of documents.

Its design principles can be summarized as:

1. domain-independence
2. light-weight logical definitions
3. alignment with popular standards, and
4. good coverage of named entities and concrete domains (i.e., people, organizations, locations, numbers, dates, addresses).

It was originally developed under the auspices of the SEKT project, and first released in 2005. It is presently maintained by Ontotext

Ontotext

Ontotext is a Bulgarian software company headquartered in Sofia. It is the semantic technology branch of . Its main domain of activity is the development of software products and solutions based on the Semantic Web languages and standards, in particular RDF, OWL and SPARQL.- Co-developer :*Open...

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