diff --git a/ontology/uco/core/core.ttl b/ontology/uco/core/core.ttl
index f0ecbace..9d59127b 100644
--- a/ontology/uco/core/core.ttl
+++ b/ontology/uco/core/core.ttl
@@ -484,6 +484,29 @@ core:hasFacet
 	rdfs:range core:Facet ;
 	.
 
+core:hasFacet-shape
+	a sh:PropertyShape ;
+	sh:path core:hasFacet ;
+	sh:sparql [
+		a sh:SPARQLConstraint ;
+		sh:message "hasFacet must not be used to link two objects to one Facet."@en ;
+		sh:select """
+			PREFIX core: <https://ontology.unifiedcyberontology.org/uco/core/>
+			PREFIX owl: <http://www.w3.org/2002/07/owl#>
+			SELECT $this ?value
+			WHERE {
+				?value core:hasFacet $this .
+				?nOtherValue core:hasFacet $this .
+				FILTER ( ?value != ?nOtherValue )
+				FILTER NOT EXISTS {
+					?value owl:sameAs|^owl:sameAs ?nOtherValue .
+				}
+			}
+			""" ;
+	] ;
+	sh:targetObjectsOf core:hasFacet ;
+	.
+
 core:id
 	a owl:DatatypeProperty ;
 	rdfs:label "id"@en ;
diff --git a/tests/examples/Makefile b/tests/examples/Makefile
index 2af81c99..87d80235 100644
--- a/tests/examples/Makefile
+++ b/tests/examples/Makefile
@@ -23,6 +23,8 @@ all: \
   action_result_PASS_validation.ttl \
   co_PASS_validation.ttl \
   co_XFAIL_validation.ttl \
+  has_facet_inverse_functional_PASS_validation.ttl \
+  has_facet_inverse_functional_XFAIL_validation.ttl \
   hash_PASS_validation.ttl \
   hash_XFAIL_validation.ttl \
   location_PASS_validation.ttl \
@@ -84,6 +86,8 @@ check: \
   action_result_PASS_validation.ttl \
   co_PASS_validation.ttl \
   co_XFAIL_validation.ttl \
+  has_facet_inverse_functional_PASS_validation.ttl \
+  has_facet_inverse_functional_XFAIL_validation.ttl \
   hash_PASS_validation.ttl \
   hash_XFAIL_validation.ttl \
   location_PASS_validation.ttl \
diff --git a/tests/examples/has_facet_inverse_functional_PASS.json b/tests/examples/has_facet_inverse_functional_PASS.json
new file mode 100644
index 00000000..573740fc
--- /dev/null
+++ b/tests/examples/has_facet_inverse_functional_PASS.json
@@ -0,0 +1,30 @@
+{
+    "@context": {
+        "kb": "http://example.org/kb/",
+        "core": "https://ontology.unifiedcyberontology.org/uco/core/",
+        "owl": "http://www.w3.org/2002/07/owl#"
+    },
+    "@graph": [
+        {
+            "@id": "kb:facet-1",
+            "@type": "core:Facet"
+        },
+        {
+            "@id": "kb:object-1",
+            "@type": "core:UcoObject",
+            "core:hasFacet": {
+                "@id": "kb:facet-1"
+            },
+            "owl:sameAs": {
+                "@id": "kb:object-2"
+            }
+        },
+        {
+            "@id": "kb:object-2",
+            "@type": "core:UcoObject",
+            "core:hasFacet": {
+                "@id": "kb:facet-1"
+            }
+        }
+    ]
+}
diff --git a/tests/examples/has_facet_inverse_functional_XFAIL.json b/tests/examples/has_facet_inverse_functional_XFAIL.json
new file mode 100644
index 00000000..46af64da
--- /dev/null
+++ b/tests/examples/has_facet_inverse_functional_XFAIL.json
@@ -0,0 +1,26 @@
+{
+    "@context": {
+        "kb": "http://example.org/kb/",
+        "core": "https://ontology.unifiedcyberontology.org/uco/core/"
+    },
+    "@graph": [
+        {
+            "@id": "kb:facet-1",
+            "@type": "core:Facet"
+        },
+        {
+            "@id": "kb:object-1",
+            "@type": "core:UcoObject",
+            "core:hasFacet": {
+                "@id": "kb:facet-1"
+            }
+        },
+        {
+            "@id": "kb:object-2",
+            "@type": "core:UcoObject",
+            "core:hasFacet": {
+                "@id": "kb:facet-1"
+            }
+        }
+    ]
+}
diff --git a/tests/examples/test_validation.py b/tests/examples/test_validation.py
index 30addef8..8a6a0222 100644
--- a/tests/examples/test_validation.py
+++ b/tests/examples/test_validation.py
@@ -177,6 +177,21 @@ def test_action_result_PASS_validation():
     g = load_validation_graph("action_result_PASS_validation.ttl", True)
     assert isinstance(g, rdflib.Graph)
 
+def test_has_facet_inverse_functional_PASS() -> None:
+    confirm_validation_results(
+      "has_facet_inverse_functional_PASS_validation.ttl",
+      True
+    )
+
+def test_has_facet_inverse_functional_XFAIL() -> None:
+    confirm_validation_results(
+      "has_facet_inverse_functional_XFAIL_validation.ttl",
+      False,
+      expected_focus_node_severities={
+        ("http://example.org/kb/facet-1", str(NS_SH.Violation))
+      }
+    )
+
 def test_hash_PASS() -> None:
     g = load_validation_graph("hash_PASS_validation.ttl", True)
     assert isinstance(g, rdflib.Graph)