diff --git a/core/api/src/main/java/org/onosproject/net/intent/constraint/AnnotationConstraint.java b/core/api/src/main/java/org/onosproject/net/intent/constraint/AnnotationConstraint.java
index 192eff5..fe91de3 100644
--- a/core/api/src/main/java/org/onosproject/net/intent/constraint/AnnotationConstraint.java
+++ b/core/api/src/main/java/org/onosproject/net/intent/constraint/AnnotationConstraint.java
@@ -76,9 +76,11 @@
     }
 
     private boolean isValid(Link link) {
-        double value = getAnnotatedValue(link, key);
-
-        return value <= threshold;
+        if (link.annotations().value(key) != null) {
+            return getAnnotatedValue(link, key) <= threshold;
+        } else {
+            return false;
+        }
     }
 
     // doesn't use LinkResourceService
diff --git a/core/api/src/test/java/org/onosproject/net/intent/constraint/AnnotationConstraintTest.java b/core/api/src/test/java/org/onosproject/net/intent/constraint/AnnotationConstraintTest.java
index afcbace..e21d480 100644
--- a/core/api/src/test/java/org/onosproject/net/intent/constraint/AnnotationConstraintTest.java
+++ b/core/api/src/test/java/org/onosproject/net/intent/constraint/AnnotationConstraintTest.java
@@ -30,6 +30,7 @@
 import static org.hamcrest.Matchers.closeTo;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.lessThan;
+import static org.hamcrest.Matchers.nullValue;
 import static org.junit.Assert.assertThat;
 import static org.onosproject.net.DefaultLinkTest.cp;
 import static org.onosproject.net.DeviceId.deviceId;
@@ -47,6 +48,7 @@
     private static final PortNumber PID1 = portNumber(1);
     private static final PortNumber PID2 = portNumber(2);
     private static final String KEY = "distance";
+    private static final String MISSING_KEY = "loss";
     private static final double VALUE = 100;
 
     private AnnotationConstraint sut;
@@ -99,4 +101,16 @@
                 .addEqualityGroup(new AnnotationConstraint("latency", 100))
                 .testEquals();
     }
+
+    /**
+     * Tests the annotated constraint is invalid and has negative cost if the key is not annotated on the link.
+     */
+    @Test
+    public void testNotAnnotated() {
+        sut = new AnnotationConstraint(MISSING_KEY, 80);
+
+        assertThat(link.annotations().value(MISSING_KEY), nullValue());
+        assertThat(sut.isValid(link, resourceContext), is(false));
+        assertThat(sut.cost(link, resourceContext), is(lessThan(0.0)));
+    }
 }