diff --git a/evaluation-suites/dependent-flags/cases/dependent-flags.json b/evaluation-suites/dependent-flags/cases/dependent-flags.json
index 44e92da..67539fe 100644
--- a/evaluation-suites/dependent-flags/cases/dependent-flags.json
+++ b/evaluation-suites/dependent-flags/cases/dependent-flags.json
@@ -339,5 +339,46 @@
     },
     "targetingKey": "dependent-cycle",
     "variationType": "STRING"
+  },
+  {
+    "description": "The 'property' key inside flagEvaluation is deliberately unknown and must be ignored; only 'key' selects the prerequisite. The unknownConditionField and unknownEvaluatorField keys must also be ignored, preserving the normal assignment and telemetry.",
+    "attributes": {},
+    "defaultValue": "caller-default",
+    "flag": "dependent-unknown-fields-root",
+    "result": {
+      "reason": "TARGETING_MATCH",
+      "value": "direct-match"
+    },
+    "targetingKey": "dependent-unknown-fields",
+    "variationType": "STRING",
+    "expectations": {
+      "noUnmatchedEvents": true,
+      "exposures": [
+        {
+          "flag": "dependent-leaf-on",
+          "allocation": "leaf-static",
+          "variant": "on",
+          "_count": 1
+        },
+        {
+          "flag": "dependent-unknown-fields-root",
+          "allocation": "dependent-match",
+          "variant": "matched",
+          "_count": 1
+        }
+      ],
+      "evaluationEvents": [
+        {
+          "flag": "dependent-leaf-on",
+          "errorCode": null,
+          "_count": 1
+        },
+        {
+          "flag": "dependent-unknown-fields-root",
+          "errorCode": null,
+          "_count": 1
+        }
+      ]
+    }
   }
 ]
diff --git a/evaluation-suites/dependent-flags/ufc-config.json b/evaluation-suites/dependent-flags/ufc-config.json
index dd15f93..cd4b480 100644
--- a/evaluation-suites/dependent-flags/ufc-config.json
+++ b/evaluation-suites/dependent-flags/ufc-config.json
@@ -6,7 +6,8 @@
     "unknownEnvironmentField": "ignored"
   },
   "evaluatorParams": {
-    "maxDependencyDepth": 2
+    "maxDependencyDepth": 2,
+    "unknownEvaluatorField": "ignored"
   },
   "flags": {
     "dependent-leaf-on": {
@@ -862,6 +863,62 @@
           "doLog": true
         }
       ]
+    },
+    "dependent-unknown-fields-root": {
+      "key": "dependent-unknown-fields-root",
+      "enabled": true,
+      "variationType": "STRING",
+      "variations": {
+        "matched": {
+          "key": "matched",
+          "value": "direct-match"
+        },
+        "fallback": {
+          "key": "fallback",
+          "value": "direct-fallback"
+        }
+      },
+      "allocations": [
+        {
+          "key": "dependent-match",
+          "rules": [
+            {
+              "conditions": [
+                {
+                  "flagEvaluation": {
+                    "key": "dependent-leaf-on",
+                    "property": "variant"
+                  },
+                  "operator": "ONE_OF",
+                  "value": [
+                    "on"
+                  ],
+                  "unknownConditionField": {
+                    "nested": true
+                  }
+                }
+              ]
+            }
+          ],
+          "splits": [
+            {
+              "variationKey": "matched",
+              "shards": []
+            }
+          ],
+          "doLog": true
+        },
+        {
+          "key": "fallback",
+          "splits": [
+            {
+              "variationKey": "fallback",
+              "shards": []
+            }
+          ],
+          "doLog": true
+        }
+      ]
     }
   }
 }