diff --git a/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java b/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
index 05dc776cf..434e2bc94 100644
--- a/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
+++ b/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
@@ -184,7 +184,7 @@ public UIDOperatorVerticle(IConfigService configService,
         this.saltRetrievalResponseHandler = saltRetrievalResponseHandler;
         this.optOutStatusApiEnabled = config.getBoolean(Const.Config.OptOutStatusApiEnabled, true);
         this.optOutStatusMaxRequestSize = config.getInteger(Const.Config.OptOutStatusMaxRequestSize, 5000);
-        this.allowLegacyAPI = config.getBoolean(Const.Config.AllowLegacyAPIProp, true);
+        this.allowLegacyAPI = config.getBoolean(Const.Config.AllowLegacyAPIProp, false);
         this.identityV3Enabled = config.getBoolean(IdentityV3Prop, false);
         this.disableOptoutToken = config.getBoolean(DisableOptoutTokenProp, false);
     }
diff --git a/src/test/java/com/uid2/operator/UIDOperatorVerticleTest.java b/src/test/java/com/uid2/operator/UIDOperatorVerticleTest.java
index b2d154b86..fa08d6b6b 100644
--- a/src/test/java/com/uid2/operator/UIDOperatorVerticleTest.java
+++ b/src/test/java/com/uid2/operator/UIDOperatorVerticleTest.java
@@ -137,6 +137,8 @@ public void deployVerticle(Vertx vertx, VertxTestContext testContext, TestInfo t
         if(testInfo.getDisplayName().equals("cstgNoPhoneSupport(Vertx, VertxTestContext)")) {
             config.put("enable_phone_support", false);
         }
+        // TODO: Remove this when we remove allow_legacy_api FF
+        config.put("allow_legacy_api", true);
         when(configService.getConfig()).thenReturn(config);
 
         this.uidOperatorVerticle = new ExtendedUIDOperatorVerticle(configService, config, config.getBoolean("client_side_token_generate"), siteProvider, clientKeyProvider, clientSideKeypairProvider, new KeyManager(keysetKeyStore, keysetProvider), saltProvider,  optOutStore, clock, statsCollectorQueue, secureLinkValidatorService, shutdownHandler::handleSaltRetrievalResponse);