diff --git a/checkout-core/api/checkout-core.api b/checkout-core/api/checkout-core.api
index ccfdf3ba63..1d622e05f9 100644
--- a/checkout-core/api/checkout-core.api
+++ b/checkout-core/api/checkout-core.api
@@ -291,7 +291,6 @@ public final class com/adyen/checkout/core/ui/validation/CardNumberValidationRes
 
 public final class com/adyen/checkout/core/ui/validation/CardNumberValidator {
 	public static final field INSTANCE Lcom/adyen/checkout/core/ui/validation/CardNumberValidator;
-	public static final field MAXIMUM_CARD_NUMBER_LENGTH I
 	public final fun validateCardNumber (Ljava/lang/String;Z)Lcom/adyen/checkout/core/ui/validation/CardNumberValidationResult;
 }
 
diff --git a/checkout-core/src/main/java/com/adyen/checkout/core/ui/validation/CardNumberValidator.kt b/checkout-core/src/main/java/com/adyen/checkout/core/ui/validation/CardNumberValidator.kt
index c1525b2408..4e2f098ee4 100644
--- a/checkout-core/src/main/java/com/adyen/checkout/core/ui/validation/CardNumberValidator.kt
+++ b/checkout-core/src/main/java/com/adyen/checkout/core/ui/validation/CardNumberValidator.kt
@@ -8,6 +8,7 @@
 
 package com.adyen.checkout.core.ui.validation
 
+import androidx.annotation.RestrictTo
 import com.adyen.checkout.core.internal.util.StringUtil
 
 object CardNumberValidator {
@@ -18,6 +19,8 @@ object CardNumberValidator {
 
     // Card Number
     private const val MINIMUM_CARD_NUMBER_LENGTH = 12
+
+    @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
     const val MAXIMUM_CARD_NUMBER_LENGTH = 19
 
     /**