diff --git a/src/main/java/com/adyen/constants/HPPConstants.java b/src/main/java/com/adyen/constants/HPPConstants.java
index 6812e578a..d424ac61f 100644
--- a/src/main/java/com/adyen/constants/HPPConstants.java
+++ b/src/main/java/com/adyen/constants/HPPConstants.java
@@ -46,6 +46,7 @@ interface Response {
         String PSP_REFERENCE = "pspReference";
         String SHOPPER_LOCALE = "shopperLocale";
         String SKIN_CODE = "skinCode";
+        String MERCHANT_RETURN_DATA = "merchantReturnData";
 
         /*
          authResult Returns the outcome of the payment.