How to restrict publishing of RDF graphs on the Semantic Web?

Question

I am trying to create a sample ontology with some dummy data using protege 5.5. But in the owl file it generated, it is showing something like this:

<?xml version="1.0"?>
<rdf:RDF xmlns="http://www.semanticweb.org/hs/ontologies/2019/3/untitled-ontology-3#"
     xml:base="http://www.semanticweb.org/hs/ontologies/2019/3/untitled-ontology-3"
     xmlns:owl="http://www.w3.org/2002/07/owl#"
     xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
     xmlns:xml="http://www.w3.org/XML/1998/namespace"
     xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
     xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#">
    <owl:Ontology rdf:about="http://www.semanticweb.org/hs/ontologies/2019/3/untitled-ontology-3"/>

Seems like this data can be accessed publicly ( http://www.semanticweb.org/hs/ontologies/2019/3/untitled-ontology-3 ). I dont wish to publish my data on the Semantic Web. Is there any way to privatise these datas? Could not find the answer on the web.

Answer 1

1. No, just because a URI shows up in an OWL or RDF file doesn't mean the data is publicly accessible. A local file on your computer is just a local file, until you upload it to a server somewhere.
2. OWL and RDF use URIs mainly just as identifiers—that is, as names that allows different programs and people to work out whether they are talking about the same thing. So, if your ontology and my ontology use the same URI for some entity, we know that we are talking about the same entity. This doesn't mean your ontology or my ontology are publicly accessible, and works even if we keep both ontologies private.
3. By convention, the owner of a URI gets to decide what entity to use a URI for. This ensures that there are no accidental clashes. Ownership of URIs is based on domain names. For example, the owner of the domain dbpedia.org (the DBpedia project) has decided that http://dbpedia.org/resource/London is a URI that names the city of London. They also happen to publish some data about London at that URI, which is a good way of letting the world know what the URI identifies.
4. Protégé is actually a bad citizen of the web by encouraging people to use URIs on a domain they don't own ( www.semanticweb.org ).
5. If you don't own a domain, you can use http://example.org/ for local experiments and private use, because that domain is explicitly allowed to be used by anyone. But if you actually decide to publish your ontology/data at some point, then you should change to a real domain.