diff --git a/ext/micrometer/src/main/java/org/glassfish/jersey/micrometer/server/JerseyKeyValues.java b/ext/micrometer/src/main/java/org/glassfish/jersey/micrometer/server/JerseyKeyValues.java
index 8e73635132..d8b6c3de96 100644
--- a/ext/micrometer/src/main/java/org/glassfish/jersey/micrometer/server/JerseyKeyValues.java
+++ b/ext/micrometer/src/main/java/org/glassfish/jersey/micrometer/server/JerseyKeyValues.java
@@ -41,6 +41,9 @@ class JerseyKeyValues {
     private static final KeyValue URI_ROOT = JerseyObservationDocumentation.JerseyLegacyLowCardinalityTags.URI
         .withValue("root");
 
+    private static final KeyValue URI_UNKNOWN = JerseyObservationDocumentation.JerseyLegacyLowCardinalityTags.URI
+            .withValue("UNKNOWN");
+
     private static final KeyValue EXCEPTION_NONE = JerseyObservationDocumentation.JerseyLegacyLowCardinalityTags.EXCEPTION
         .withValue("None");
 
@@ -106,6 +109,9 @@ static KeyValue uri(RequestEvent event) {
             }
         }
         String matchingPattern = JerseyTags.getMatchingPattern(event);
+        if (matchingPattern == null) {
+            return URI_UNKNOWN;
+        }
         if (matchingPattern.equals("/")) {
             return URI_ROOT;
         }