diff --git a/publish/src/rdf/ontology.rs b/publish/src/rdf/ontology.rs
index ce6f494..d72ab1e 100644
--- a/publish/src/rdf/ontology.rs
+++ b/publish/src/rdf/ontology.rs
@@ -149,34 +149,10 @@ SELECT DISTINCT ?subject ?label ?comment ?read_only {{
     }
 
     fn memoize(ontology: &mut Ontology) {
-        /*// Read-only properties
-        for quad in ontology.dataset.quads_for_pattern(
-            None,
-            Some(rdf::TYPE),
-            Some(TermRef::NamedNode(GL_READ_ONLY)),
-            None,
-        ) {
-            if let NamedOrBlankNodeRef::NamedNode(subject) = quad.subject {
-                ontology.read_only_properties.insert(subject.into_owned());
-            }
-        }
-
-        // Read-only classes
-        for quad in ontology.dataset.quads_for_pattern(
-            None,
-            Some(rdfs::SUB_CLASS_OF),
-            Some(TermRef::NamedNode(GL_READ_ONLY)),
-            None,
-        ) {
-            if let NamedOrBlankNodeRef::NamedNode(subject) = quad.subject {
-                ontology.read_only_classes.insert(subject.into_owned());
-            }
-        }
-
         // Full-text search index field names
         for quad in ontology
             .dataset
-            .quads_for_pattern(None, Some(GL_INDEXED_BY_FIELD), None, None)
+            .quads_for_pattern(None, Some(gl::INDEXED_BY_FIELD), None, None)
         {
             if let NamedOrBlankNodeRef::NamedNode(subject) = quad.subject
                 && let TermRef::Literal(literal) = quad.object
@@ -190,7 +166,7 @@ SELECT DISTINCT ?subject ?label ?comment ?read_only {{
         // Catalog IDs (used to quickly filter full-text search results)
         for quad in ontology
             .dataset
-            .quads_for_pattern(None, Some(GL_CATALOG_ID), None, None)
+            .quads_for_pattern(None, Some(gl::CATALOG_ID), None, None)
         {
             if let NamedOrBlankNodeRef::NamedNode(subject) = quad.subject
                 && let TermRef::Literal(literal) = quad.object
@@ -200,7 +176,7 @@ SELECT DISTINCT ?subject ?label ?comment ?read_only {{
                     ontology.catalog_ids.insert(subject.into_owned(), value);
                 }
             }
-        }*/
+        }
     }
 
     pub fn build(&mut self) -> error::Result<Ontology> {
@@ -237,8 +213,6 @@ SELECT DISTINCT ?subject ?label ?comment ?read_only {{
             prefixes,
             properties,
             classes,
-            read_only_properties: HashSet::new(),
-            read_only_classes: HashSet::new(),
             field_map: HashMap::new(),
             catalog_ids: HashMap::new(),
         };
@@ -248,7 +222,7 @@ SELECT DISTINCT ?subject ?label ?comment ?read_only {{
     }
 }
 
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 struct IriInformation {
     label: Option<String>,
     comment: Option<String>,
@@ -260,8 +234,6 @@ pub struct Ontology {
     prefixes: HashMap<String, String>,
     properties: HashMap<NamedNode, IriInformation>,
     classes: HashMap<NamedNode, IriInformation>,
-    read_only_properties: HashSet<NamedNode>,
-    read_only_classes: HashSet<NamedNode>,
     field_map: HashMap<NamedNode, String>,
     catalog_ids: HashMap<NamedNode, u64>,
 }
@@ -394,24 +366,36 @@ SELECT ?subject ?label ?comment WHERE {
     pub fn is_read_only<'a>(&self, triple: impl Into<TripleRef<'a>>) -> bool {
         let triple = triple.into();
         let read_only_property = self
-            .read_only_properties
-            .contains(&triple.predicate.into_owned());
+            .properties
+            .get(&triple.predicate.into_owned())
+            .map(|info| info.read_only)
+            .unwrap_or(false);
+
         let read_only_class = match (triple.predicate, triple.object) {
             (rdf::TYPE, TermRef::NamedNode(node)) => {
-                self.read_only_classes.contains(&node.into_owned())
+                self.classes
+                    .get(&node.into_owned())
+                    .map(|info| info.read_only)
+                    .unwrap_or(false)
             }
             _ => false,
         };
+
         read_only_property || read_only_class
     }
 
     pub fn exclude_read_only_predicate(&self) -> impl Fn(TripleRef<'_>) -> bool + 'static {
-        let classes = self.read_only_classes.clone();
-        let properties = self.read_only_properties.clone();
+        let classes = self.classes.clone();
+        let properties = self.properties.clone();
         move |triple| {
-            let read_only_property = properties.contains(&triple.predicate.into_owned());
+            let read_only_property = properties.get(&triple.predicate.into_owned())
+                .map(|info| info.read_only)
+                .unwrap_or(false);
+
             let read_only_class = match (triple.predicate, triple.object) {
-                (rdf::TYPE, TermRef::NamedNode(node)) => classes.contains(&node.into_owned()),
+                (rdf::TYPE, TermRef::NamedNode(node)) => classes.get(&node.into_owned())
+                    .map(|info| info.read_only)
+                    .unwrap_or(false),
                 _ => false,
             };
             !(read_only_property || read_only_class)