diff --git a/src/config/spotbugs/exclude.xml b/src/config/spotbugs/exclude.xml
index 928020f9..0a97cd4e 100644
--- a/src/config/spotbugs/exclude.xml
+++ b/src/config/spotbugs/exclude.xml
@@ -43,4 +43,14 @@
         <Source name="DefaultTypingFixture.java"/>
     </Match>
 
+    <!-- Micrometer holds gauge referents weakly, so a gauge whose source object is collected
+         reports NaN forever afterwards. The only way to assert that the notification metrics do
+         NOT have that defect is to provoke a collection, which is what DM_GC flags. Scoped to the
+         single test method that does it; a System.gc() anywhere else remains reportable. -->
+    <Match>
+        <Bug pattern="DM_GC"/>
+        <Class name="dev.caskeleton.bootstrap.notification.observation.NotificationObservationTest"/>
+        <Method name="aGaugeKeepsReportingAfterGarbageCollectionInsteadOfDecayingToNaN"/>
+    </Match>
+
 </FindBugsFilter>