diff --git a/metager/app/Models/Authorization/KeyAuthorization.php b/metager/app/Models/Authorization/KeyAuthorization.php
index 3e146dc253c6787aa671f4bb213b1259655f056b..1dfe10779fc82c45ff914dec19e3dacf1b4b2b0e 100644
--- a/metager/app/Models/Authorization/KeyAuthorization.php
+++ b/metager/app/Models/Authorization/KeyAuthorization.php
@@ -2,7 +2,9 @@
 
 namespace App\Models\Authorization;
 
+use App\PrometheusExporter;
 use Illuminate\Support\Facades\Redis;
+use Prometheus\CollectorRegistry;
 
 class KeyAuthorization extends Authorization
 {
@@ -87,6 +89,10 @@ class KeyAuthorization extends Authorization
         $mission = json_encode($mission);
         Redis::rpush(\App\MetaGer::FETCHQUEUE_KEY, $mission);
 
+        if (config('metager.metager.keys.uni_mainz') === $this->key) {
+            PrometheusExporter::UpdateMainzKeyStatus($this->availableTokens);
+        }
+
         return true;
     }
     /**
diff --git a/metager/app/PrometheusExporter.php b/metager/app/PrometheusExporter.php
index c686f2479dbc1411e358f95d0c614ae28d80487f..8bf1da97c25eebf96c1d83b15ee297cdcf50ff92 100644
--- a/metager/app/PrometheusExporter.php
+++ b/metager/app/PrometheusExporter.php
@@ -73,4 +73,10 @@ class PrometheusExporter
         $counter = $registry->getOrRegisterCounter("metager", "key_used", "Counts MetaGer Key Usage", ["searchengine", "cached"]);
         $counter->inc([$engine, json_encode($cached)]);
     }
+    public static function UpdateMainzKeyStatus($tokens)
+    {
+        $registry = CollectorRegistry::getDefault();
+        $gauge = $registry->getOrRegisterGauge("metager", "key", "Tracks status of the Mainz Key", ["owner"]);
+        $gauge->set($tokens, ["mainz"]);
+    }
 }
\ No newline at end of file