diff --git a/Reflect.ts b/Reflect.ts
index b3468b8..dea1eb1 100644
--- a/Reflect.ts
+++ b/Reflect.ts
@@ -1497,7 +1497,11 @@ namespace Reflect {
             if (!IsUndefined(registrySymbol) &&
                 typeof root.Reflect !== "undefined" &&
                 !(registrySymbol in root.Reflect) &&
-                typeof root.Reflect.defineMetadata === "function") {
+                typeof root.Reflect.defineMetadata === "function" &&
+                typeof root.Reflect.hasOwnMetadata === "function" &&
+                typeof root.Reflect.getOwnMetadata === "function" &&
+                typeof root.Reflect.getOwnMetadataKeys === "function" &&
+                typeof root.Reflect.deleteMetadata === "function") {
                 // interoperate with older version of `reflect-metadata` that did not support a registry.
                 fallback = CreateFallbackProvider(root.Reflect);
             }
diff --git a/ReflectLite.ts b/ReflectLite.ts
index 858da75..5e523e2 100644
--- a/ReflectLite.ts
+++ b/ReflectLite.ts
@@ -1457,7 +1457,11 @@ namespace Reflect {
             if (!IsUndefined(registrySymbol) &&
                 typeof root.Reflect !== "undefined" &&
                 !(registrySymbol in root.Reflect) &&
-                typeof root.Reflect.defineMetadata === "function") {
+                typeof root.Reflect.defineMetadata === "function" &&
+                typeof root.Reflect.hasOwnMetadata === "function" &&
+                typeof root.Reflect.getOwnMetadata === "function" &&
+                typeof root.Reflect.getOwnMetadataKeys === "function" &&
+                typeof root.Reflect.deleteMetadata === "function") {
                 // interoperate with older version of `reflect-metadata` that did not support a registry.
                 fallback = CreateFallbackProvider(root.Reflect);
             }
diff --git a/ReflectNoConflict.ts b/ReflectNoConflict.ts
index f7707fd..0d50e76 100644
--- a/ReflectNoConflict.ts
+++ b/ReflectNoConflict.ts
@@ -1334,7 +1334,11 @@ function CreateMetadataRegistry(): MetadataRegistry {
     if (!IsUndefined(registrySymbol) &&
         typeof Reflect !== "undefined" &&
         !(registrySymbol in Reflect) &&
-        typeof Reflect.defineMetadata === "function") {
+        typeof Reflect.defineMetadata === "function" &&
+        typeof Reflect.hasOwnMetadata === "function" &&
+        typeof Reflect.getOwnMetadata === "function" &&
+        typeof Reflect.getOwnMetadataKeys === "function" &&
+        typeof Reflect.deleteMetadata === "function") {
         // interoperate with older version of `reflect-metadata` that did not support a registry.
         fallback = CreateFallbackProvider(Reflect);
     }
diff --git a/test/registry.ts b/test/registry.ts
index 43ca659..8b9645e 100644
--- a/test/registry.ts
+++ b/test/registry.ts
@@ -115,5 +115,21 @@ for (const { name, header, context } of suites) {
             assert.isDefined(provider2);
             assert.strictEqual(provider1, provider2);
         });
+        it("ignores incomplete implementation", () => {
+            const { missing, value } = script({ ...context })`
+                Reflect.defineMetadata = function() {};
+
+                {
+                    ${header}
+
+                    const obj = {};
+                    exports.missing = Reflect.getOwnMetadata("a", obj);
+                    Reflect.defineMetadata("a", 1, obj);
+                    exports.value = Reflect.getOwnMetadata("a", obj);
+                }
+            `;
+            assert.isUndefined(missing);
+            assert.strictEqual(value, 1);
+        });
     });
 }
\ No newline at end of file