diff --git a/changes.md b/changes.md
index 11735e4815d..8debd276782 100644
--- a/changes.md
+++ b/changes.md
@@ -1,20 +1,19 @@
 **Api changes**
 
 <details>
-<summary>Added Property(s)</summary>
+<summary>Required Property(s)</summary>
 
-- added property `isActive` to type `DiscountGroup`
-- added property `isActive` to type `DiscountGroupDraft`
-</details>
-
-
-<details>
-<summary>Added Type(s)</summary>
-
-- added type `DiscountGroupSetIsActiveAction`
-- added type `MaxDiscountGroupsReachedError`
-- added type `GraphQLMaxDiscountGroupsReachedError`
-- added type `DiscountGroupIsActiveSetMessage`
-- added type `DiscountGroupIsActiveSetMessagePayload`
+- changed property `variantSelection` of type `ProductSelectionProductAddedMessage` to be optional
+- changed property `variantExclusion` of type `ProductSelectionProductExcludedMessage` to be optional
+- changed property `oldVariantExclusion` of type `ProductSelectionVariantExclusionChangedMessage` to be optional
+- changed property `newVariantExclusion` of type `ProductSelectionVariantExclusionChangedMessage` to be optional
+- changed property `oldVariantSelection` of type `ProductSelectionVariantSelectionChangedMessage` to be optional
+- changed property `newVariantSelection` of type `ProductSelectionVariantSelectionChangedMessage` to be optional
+- changed property `variantSelection` of type `ProductSelectionProductAddedMessagePayload` to be optional
+- changed property `variantExclusion` of type `ProductSelectionProductExcludedMessagePayload` to be optional
+- changed property `oldVariantExclusion` of type `ProductSelectionVariantExclusionChangedMessagePayload` to be optional
+- changed property `newVariantExclusion` of type `ProductSelectionVariantExclusionChangedMessagePayload` to be optional
+- changed property `oldVariantSelection` of type `ProductSelectionVariantSelectionChangedMessagePayload` to be optional
+- changed property `newVariantSelection` of type `ProductSelectionVariantSelectionChangedMessagePayload` to be optional
 </details>
 
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessage.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessage.java
index 3cab5891b07..a6e4ba46e3f 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessage.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessage.java
@@ -33,7 +33,6 @@
  *             .resource(resourceBuilder -> resourceBuilder)
  *             .resourceVersion(0.3)
  *             .product(productBuilder -> productBuilder)
- *             .variantSelection(variantSelectionBuilder -> variantSelectionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -61,7 +60,6 @@ public interface ProductSelectionProductAddedMessage extends Message {
      *  <p>Product Variant Selection after the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionAddProductAction" rel="nofollow">Add Product</a> update action.</p>
      * @return variantSelection
      */
-    @NotNull
     @Valid
     @JsonProperty("variantSelection")
     public ProductVariantSelection getVariantSelection();
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessageBuilder.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessageBuilder.java
index ca88e41fab3..8636f6639f0 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessageBuilder.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessageBuilder.java
@@ -24,7 +24,6 @@
  *             .resource(resourceBuilder -> resourceBuilder)
  *             .resourceVersion(0.3)
  *             .product(productBuilder -> productBuilder)
- *             .variantSelection(variantSelectionBuilder -> variantSelectionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -57,6 +56,7 @@ public class ProductSelectionProductAddedMessageBuilder implements Builder<Produ
 
     private com.commercetools.api.models.product.ProductReference product;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantSelection variantSelection;
 
     /**
@@ -303,7 +303,7 @@ public ProductSelectionProductAddedMessageBuilder product(
      */
 
     public ProductSelectionProductAddedMessageBuilder variantSelection(
-            final com.commercetools.api.models.product_selection.ProductVariantSelection variantSelection) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantSelection variantSelection) {
         this.variantSelection = variantSelection;
         return this;
     }
@@ -429,6 +429,7 @@ public com.commercetools.api.models.product.ProductReference getProduct() {
      * @return variantSelection
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantSelection getVariantSelection() {
         return this.variantSelection;
     }
@@ -449,8 +450,6 @@ public ProductSelectionProductAddedMessage build() {
         Objects.requireNonNull(resourceVersion,
             ProductSelectionProductAddedMessage.class + ": resourceVersion is missing");
         Objects.requireNonNull(product, ProductSelectionProductAddedMessage.class + ": product is missing");
-        Objects.requireNonNull(variantSelection,
-            ProductSelectionProductAddedMessage.class + ": variantSelection is missing");
         return new ProductSelectionProductAddedMessageImpl(id, version, createdAt, lastModifiedAt, lastModifiedBy,
             createdBy, sequenceNumber, resource, resourceVersion, resourceUserProvidedIdentifiers, product,
             variantSelection);
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessagePayload.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessagePayload.java
index ed3afb6602e..cff82cbde92 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessagePayload.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessagePayload.java
@@ -26,7 +26,6 @@
  * <pre><code class='java'>
  *     ProductSelectionProductAddedMessagePayload productSelectionProductAddedMessagePayload = ProductSelectionProductAddedMessagePayload.builder()
  *             .product(productBuilder -> productBuilder)
- *             .variantSelection(variantSelectionBuilder -> variantSelectionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -54,7 +53,6 @@ public interface ProductSelectionProductAddedMessagePayload extends MessagePaylo
      *  <p>Product Variant Selection after the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionAddProductAction" rel="nofollow">Add Product</a> update action.</p>
      * @return variantSelection
      */
-    @NotNull
     @Valid
     @JsonProperty("variantSelection")
     public ProductVariantSelection getVariantSelection();
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessagePayloadBuilder.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessagePayloadBuilder.java
index 72814a3f0df..782d0201682 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessagePayloadBuilder.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductAddedMessagePayloadBuilder.java
@@ -4,6 +4,8 @@
 import java.util.*;
 import java.util.function.Function;
 
+import javax.annotation.Nullable;
+
 import io.vrap.rmf.base.client.Builder;
 import io.vrap.rmf.base.client.utils.Generated;
 
@@ -15,7 +17,6 @@
  * <pre><code class='java'>
  *     ProductSelectionProductAddedMessagePayload productSelectionProductAddedMessagePayload = ProductSelectionProductAddedMessagePayload.builder()
  *             .product(productBuilder -> productBuilder)
- *             .variantSelection(variantSelectionBuilder -> variantSelectionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -26,6 +27,7 @@ public class ProductSelectionProductAddedMessagePayloadBuilder
 
     private com.commercetools.api.models.product.ProductReference product;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantSelection variantSelection;
 
     /**
@@ -71,7 +73,7 @@ public ProductSelectionProductAddedMessagePayloadBuilder product(
      */
 
     public ProductSelectionProductAddedMessagePayloadBuilder variantSelection(
-            final com.commercetools.api.models.product_selection.ProductVariantSelection variantSelection) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantSelection variantSelection) {
         this.variantSelection = variantSelection;
         return this;
     }
@@ -104,6 +106,7 @@ public com.commercetools.api.models.product.ProductReference getProduct() {
      * @return variantSelection
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantSelection getVariantSelection() {
         return this.variantSelection;
     }
@@ -114,8 +117,6 @@ public com.commercetools.api.models.product_selection.ProductVariantSelection ge
      */
     public ProductSelectionProductAddedMessagePayload build() {
         Objects.requireNonNull(product, ProductSelectionProductAddedMessagePayload.class + ": product is missing");
-        Objects.requireNonNull(variantSelection,
-            ProductSelectionProductAddedMessagePayload.class + ": variantSelection is missing");
         return new ProductSelectionProductAddedMessagePayloadImpl(product, variantSelection);
     }
 
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessage.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessage.java
index 3d0a8471f28..28f63e5cf61 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessage.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessage.java
@@ -33,7 +33,6 @@
  *             .resource(resourceBuilder -> resourceBuilder)
  *             .resourceVersion(0.3)
  *             .product(productBuilder -> productBuilder)
- *             .variantExclusion(variantExclusionBuilder -> variantExclusionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -61,7 +60,6 @@ public interface ProductSelectionProductExcludedMessage extends Message {
      *  <p>Product Variant Exclusion after the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionExcludeProductAction" rel="nofollow">Exclude Product</a> update action.</p>
      * @return variantExclusion
      */
-    @NotNull
     @Valid
     @JsonProperty("variantExclusion")
     public ProductVariantExclusion getVariantExclusion();
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessageBuilder.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessageBuilder.java
index fafdfcc08bd..79d60bad4f6 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessageBuilder.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessageBuilder.java
@@ -24,7 +24,6 @@
  *             .resource(resourceBuilder -> resourceBuilder)
  *             .resourceVersion(0.3)
  *             .product(productBuilder -> productBuilder)
- *             .variantExclusion(variantExclusionBuilder -> variantExclusionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -57,6 +56,7 @@ public class ProductSelectionProductExcludedMessageBuilder implements Builder<Pr
 
     private com.commercetools.api.models.product.ProductReference product;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantExclusion variantExclusion;
 
     /**
@@ -330,7 +330,7 @@ public ProductSelectionProductExcludedMessageBuilder withVariantExclusion(
      */
 
     public ProductSelectionProductExcludedMessageBuilder variantExclusion(
-            final com.commercetools.api.models.product_selection.ProductVariantExclusion variantExclusion) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantExclusion variantExclusion) {
         this.variantExclusion = variantExclusion;
         return this;
     }
@@ -442,6 +442,7 @@ public com.commercetools.api.models.product.ProductReference getProduct() {
      * @return variantExclusion
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantExclusion getVariantExclusion() {
         return this.variantExclusion;
     }
@@ -462,8 +463,6 @@ public ProductSelectionProductExcludedMessage build() {
         Objects.requireNonNull(resourceVersion,
             ProductSelectionProductExcludedMessage.class + ": resourceVersion is missing");
         Objects.requireNonNull(product, ProductSelectionProductExcludedMessage.class + ": product is missing");
-        Objects.requireNonNull(variantExclusion,
-            ProductSelectionProductExcludedMessage.class + ": variantExclusion is missing");
         return new ProductSelectionProductExcludedMessageImpl(id, version, createdAt, lastModifiedAt, lastModifiedBy,
             createdBy, sequenceNumber, resource, resourceVersion, resourceUserProvidedIdentifiers, product,
             variantExclusion);
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessagePayload.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessagePayload.java
index ee27eddab2d..3c94bc624ad 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessagePayload.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessagePayload.java
@@ -26,7 +26,6 @@
  * <pre><code class='java'>
  *     ProductSelectionProductExcludedMessagePayload productSelectionProductExcludedMessagePayload = ProductSelectionProductExcludedMessagePayload.builder()
  *             .product(productBuilder -> productBuilder)
- *             .variantExclusion(variantExclusionBuilder -> variantExclusionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -54,7 +53,6 @@ public interface ProductSelectionProductExcludedMessagePayload extends MessagePa
      *  <p>Product Variant Exclusion after the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionExcludeProductAction" rel="nofollow">Exclude Product</a> update action.</p>
      * @return variantExclusion
      */
-    @NotNull
     @Valid
     @JsonProperty("variantExclusion")
     public ProductVariantExclusion getVariantExclusion();
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessagePayloadBuilder.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessagePayloadBuilder.java
index ea97b02a467..2cefc1d565f 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessagePayloadBuilder.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionProductExcludedMessagePayloadBuilder.java
@@ -4,6 +4,8 @@
 import java.util.*;
 import java.util.function.Function;
 
+import javax.annotation.Nullable;
+
 import io.vrap.rmf.base.client.Builder;
 import io.vrap.rmf.base.client.utils.Generated;
 
@@ -15,7 +17,6 @@
  * <pre><code class='java'>
  *     ProductSelectionProductExcludedMessagePayload productSelectionProductExcludedMessagePayload = ProductSelectionProductExcludedMessagePayload.builder()
  *             .product(productBuilder -> productBuilder)
- *             .variantExclusion(variantExclusionBuilder -> variantExclusionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -26,6 +27,7 @@ public class ProductSelectionProductExcludedMessagePayloadBuilder
 
     private com.commercetools.api.models.product.ProductReference product;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantExclusion variantExclusion;
 
     /**
@@ -98,7 +100,7 @@ public ProductSelectionProductExcludedMessagePayloadBuilder withVariantExclusion
      */
 
     public ProductSelectionProductExcludedMessagePayloadBuilder variantExclusion(
-            final com.commercetools.api.models.product_selection.ProductVariantExclusion variantExclusion) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantExclusion variantExclusion) {
         this.variantExclusion = variantExclusion;
         return this;
     }
@@ -117,6 +119,7 @@ public com.commercetools.api.models.product.ProductReference getProduct() {
      * @return variantExclusion
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantExclusion getVariantExclusion() {
         return this.variantExclusion;
     }
@@ -127,8 +130,6 @@ public com.commercetools.api.models.product_selection.ProductVariantExclusion ge
      */
     public ProductSelectionProductExcludedMessagePayload build() {
         Objects.requireNonNull(product, ProductSelectionProductExcludedMessagePayload.class + ": product is missing");
-        Objects.requireNonNull(variantExclusion,
-            ProductSelectionProductExcludedMessagePayload.class + ": variantExclusion is missing");
         return new ProductSelectionProductExcludedMessagePayloadImpl(product, variantExclusion);
     }
 
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessage.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessage.java
index eefc29cf91f..c2dfb182a62 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessage.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessage.java
@@ -33,8 +33,6 @@
  *             .resource(resourceBuilder -> resourceBuilder)
  *             .resourceVersion(0.3)
  *             .product(productBuilder -> productBuilder)
- *             .oldVariantExclusion(oldVariantExclusionBuilder -> oldVariantExclusionBuilder)
- *             .newVariantExclusion(newVariantExclusionBuilder -> newVariantExclusionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -62,7 +60,6 @@ public interface ProductSelectionVariantExclusionChangedMessage extends Message
      *  <p>Product Variant Exclusion before the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionSetVariantExclusionAction" rel="nofollow">Set Variant Exclusion</a> update action.</p>
      * @return oldVariantExclusion
      */
-    @NotNull
     @Valid
     @JsonProperty("oldVariantExclusion")
     public ProductVariantExclusion getOldVariantExclusion();
@@ -71,7 +68,6 @@ public interface ProductSelectionVariantExclusionChangedMessage extends Message
      *  <p>Product Variant Exclusion after the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionSetVariantExclusionAction" rel="nofollow">Set Variant Exclusion</a> update action.</p>
      * @return newVariantExclusion
      */
-    @NotNull
     @Valid
     @JsonProperty("newVariantExclusion")
     public ProductVariantExclusion getNewVariantExclusion();
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessageBuilder.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessageBuilder.java
index f89b47f9c83..f9acb17e133 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessageBuilder.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessageBuilder.java
@@ -24,8 +24,6 @@
  *             .resource(resourceBuilder -> resourceBuilder)
  *             .resourceVersion(0.3)
  *             .product(productBuilder -> productBuilder)
- *             .oldVariantExclusion(oldVariantExclusionBuilder -> oldVariantExclusionBuilder)
- *             .newVariantExclusion(newVariantExclusionBuilder -> newVariantExclusionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -59,8 +57,10 @@ public class ProductSelectionVariantExclusionChangedMessageBuilder
 
     private com.commercetools.api.models.product.ProductReference product;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantExclusion oldVariantExclusion;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantExclusion newVariantExclusion;
 
     /**
@@ -335,7 +335,7 @@ public ProductSelectionVariantExclusionChangedMessageBuilder withOldVariantExclu
      */
 
     public ProductSelectionVariantExclusionChangedMessageBuilder oldVariantExclusion(
-            final com.commercetools.api.models.product_selection.ProductVariantExclusion oldVariantExclusion) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantExclusion oldVariantExclusion) {
         this.oldVariantExclusion = oldVariantExclusion;
         return this;
     }
@@ -374,7 +374,7 @@ public ProductSelectionVariantExclusionChangedMessageBuilder withNewVariantExclu
      */
 
     public ProductSelectionVariantExclusionChangedMessageBuilder newVariantExclusion(
-            final com.commercetools.api.models.product_selection.ProductVariantExclusion newVariantExclusion) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantExclusion newVariantExclusion) {
         this.newVariantExclusion = newVariantExclusion;
         return this;
     }
@@ -486,6 +486,7 @@ public com.commercetools.api.models.product.ProductReference getProduct() {
      * @return oldVariantExclusion
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantExclusion getOldVariantExclusion() {
         return this.oldVariantExclusion;
     }
@@ -495,6 +496,7 @@ public com.commercetools.api.models.product_selection.ProductVariantExclusion ge
      * @return newVariantExclusion
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantExclusion getNewVariantExclusion() {
         return this.newVariantExclusion;
     }
@@ -517,10 +519,6 @@ public ProductSelectionVariantExclusionChangedMessage build() {
         Objects.requireNonNull(resourceVersion,
             ProductSelectionVariantExclusionChangedMessage.class + ": resourceVersion is missing");
         Objects.requireNonNull(product, ProductSelectionVariantExclusionChangedMessage.class + ": product is missing");
-        Objects.requireNonNull(oldVariantExclusion,
-            ProductSelectionVariantExclusionChangedMessage.class + ": oldVariantExclusion is missing");
-        Objects.requireNonNull(newVariantExclusion,
-            ProductSelectionVariantExclusionChangedMessage.class + ": newVariantExclusion is missing");
         return new ProductSelectionVariantExclusionChangedMessageImpl(id, version, createdAt, lastModifiedAt,
             lastModifiedBy, createdBy, sequenceNumber, resource, resourceVersion, resourceUserProvidedIdentifiers,
             product, oldVariantExclusion, newVariantExclusion);
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessagePayload.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessagePayload.java
index d2b4ac2a107..18e1960ac4d 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessagePayload.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessagePayload.java
@@ -26,8 +26,6 @@
  * <pre><code class='java'>
  *     ProductSelectionVariantExclusionChangedMessagePayload productSelectionVariantExclusionChangedMessagePayload = ProductSelectionVariantExclusionChangedMessagePayload.builder()
  *             .product(productBuilder -> productBuilder)
- *             .oldVariantExclusion(oldVariantExclusionBuilder -> oldVariantExclusionBuilder)
- *             .newVariantExclusion(newVariantExclusionBuilder -> newVariantExclusionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -55,7 +53,6 @@ public interface ProductSelectionVariantExclusionChangedMessagePayload extends M
      *  <p>Product Variant Exclusion before the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionSetVariantExclusionAction" rel="nofollow">Set Variant Exclusion</a> update action.</p>
      * @return oldVariantExclusion
      */
-    @NotNull
     @Valid
     @JsonProperty("oldVariantExclusion")
     public ProductVariantExclusion getOldVariantExclusion();
@@ -64,7 +61,6 @@ public interface ProductSelectionVariantExclusionChangedMessagePayload extends M
      *  <p>Product Variant Exclusion after the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionSetVariantExclusionAction" rel="nofollow">Set Variant Exclusion</a> update action.</p>
      * @return newVariantExclusion
      */
-    @NotNull
     @Valid
     @JsonProperty("newVariantExclusion")
     public ProductVariantExclusion getNewVariantExclusion();
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessagePayloadBuilder.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessagePayloadBuilder.java
index 608cf68abc8..b0e560bf89d 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessagePayloadBuilder.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantExclusionChangedMessagePayloadBuilder.java
@@ -4,6 +4,8 @@
 import java.util.*;
 import java.util.function.Function;
 
+import javax.annotation.Nullable;
+
 import io.vrap.rmf.base.client.Builder;
 import io.vrap.rmf.base.client.utils.Generated;
 
@@ -15,8 +17,6 @@
  * <pre><code class='java'>
  *     ProductSelectionVariantExclusionChangedMessagePayload productSelectionVariantExclusionChangedMessagePayload = ProductSelectionVariantExclusionChangedMessagePayload.builder()
  *             .product(productBuilder -> productBuilder)
- *             .oldVariantExclusion(oldVariantExclusionBuilder -> oldVariantExclusionBuilder)
- *             .newVariantExclusion(newVariantExclusionBuilder -> newVariantExclusionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -27,8 +27,10 @@ public class ProductSelectionVariantExclusionChangedMessagePayloadBuilder
 
     private com.commercetools.api.models.product.ProductReference product;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantExclusion oldVariantExclusion;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantExclusion newVariantExclusion;
 
     /**
@@ -101,7 +103,7 @@ public ProductSelectionVariantExclusionChangedMessagePayloadBuilder withOldVaria
      */
 
     public ProductSelectionVariantExclusionChangedMessagePayloadBuilder oldVariantExclusion(
-            final com.commercetools.api.models.product_selection.ProductVariantExclusion oldVariantExclusion) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantExclusion oldVariantExclusion) {
         this.oldVariantExclusion = oldVariantExclusion;
         return this;
     }
@@ -140,7 +142,7 @@ public ProductSelectionVariantExclusionChangedMessagePayloadBuilder withNewVaria
      */
 
     public ProductSelectionVariantExclusionChangedMessagePayloadBuilder newVariantExclusion(
-            final com.commercetools.api.models.product_selection.ProductVariantExclusion newVariantExclusion) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantExclusion newVariantExclusion) {
         this.newVariantExclusion = newVariantExclusion;
         return this;
     }
@@ -159,6 +161,7 @@ public com.commercetools.api.models.product.ProductReference getProduct() {
      * @return oldVariantExclusion
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantExclusion getOldVariantExclusion() {
         return this.oldVariantExclusion;
     }
@@ -168,6 +171,7 @@ public com.commercetools.api.models.product_selection.ProductVariantExclusion ge
      * @return newVariantExclusion
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantExclusion getNewVariantExclusion() {
         return this.newVariantExclusion;
     }
@@ -179,10 +183,6 @@ public com.commercetools.api.models.product_selection.ProductVariantExclusion ge
     public ProductSelectionVariantExclusionChangedMessagePayload build() {
         Objects.requireNonNull(product,
             ProductSelectionVariantExclusionChangedMessagePayload.class + ": product is missing");
-        Objects.requireNonNull(oldVariantExclusion,
-            ProductSelectionVariantExclusionChangedMessagePayload.class + ": oldVariantExclusion is missing");
-        Objects.requireNonNull(newVariantExclusion,
-            ProductSelectionVariantExclusionChangedMessagePayload.class + ": newVariantExclusion is missing");
         return new ProductSelectionVariantExclusionChangedMessagePayloadImpl(product, oldVariantExclusion,
             newVariantExclusion);
     }
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessage.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessage.java
index d0b1a888ba8..a58aafb5e7e 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessage.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessage.java
@@ -33,8 +33,6 @@
  *             .resource(resourceBuilder -> resourceBuilder)
  *             .resourceVersion(0.3)
  *             .product(productBuilder -> productBuilder)
- *             .oldVariantSelection(oldVariantSelectionBuilder -> oldVariantSelectionBuilder)
- *             .newVariantSelection(newVariantSelectionBuilder -> newVariantSelectionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -62,7 +60,6 @@ public interface ProductSelectionVariantSelectionChangedMessage extends Message
      *  <p>Product Variant Selection before the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionSetVariantSelectionAction" rel="nofollow">Set Variant Selection</a> update action.</p>
      * @return oldVariantSelection
      */
-    @NotNull
     @Valid
     @JsonProperty("oldVariantSelection")
     public ProductVariantSelection getOldVariantSelection();
@@ -71,7 +68,6 @@ public interface ProductSelectionVariantSelectionChangedMessage extends Message
      *  <p>Product Variant Selection after the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionSetVariantSelectionAction" rel="nofollow">Set Variant Selection</a> update action.</p>
      * @return newVariantSelection
      */
-    @NotNull
     @Valid
     @JsonProperty("newVariantSelection")
     public ProductVariantSelection getNewVariantSelection();
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessageBuilder.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessageBuilder.java
index e31e5d333cd..858ceed39bb 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessageBuilder.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessageBuilder.java
@@ -24,8 +24,6 @@
  *             .resource(resourceBuilder -> resourceBuilder)
  *             .resourceVersion(0.3)
  *             .product(productBuilder -> productBuilder)
- *             .oldVariantSelection(oldVariantSelectionBuilder -> oldVariantSelectionBuilder)
- *             .newVariantSelection(newVariantSelectionBuilder -> newVariantSelectionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -59,8 +57,10 @@ public class ProductSelectionVariantSelectionChangedMessageBuilder
 
     private com.commercetools.api.models.product.ProductReference product;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantSelection oldVariantSelection;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantSelection newVariantSelection;
 
     /**
@@ -308,7 +308,7 @@ public ProductSelectionVariantSelectionChangedMessageBuilder product(
      */
 
     public ProductSelectionVariantSelectionChangedMessageBuilder oldVariantSelection(
-            final com.commercetools.api.models.product_selection.ProductVariantSelection oldVariantSelection) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantSelection oldVariantSelection) {
         this.oldVariantSelection = oldVariantSelection;
         return this;
     }
@@ -334,7 +334,7 @@ public ProductSelectionVariantSelectionChangedMessageBuilder oldVariantSelection
      */
 
     public ProductSelectionVariantSelectionChangedMessageBuilder newVariantSelection(
-            final com.commercetools.api.models.product_selection.ProductVariantSelection newVariantSelection) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantSelection newVariantSelection) {
         this.newVariantSelection = newVariantSelection;
         return this;
     }
@@ -460,6 +460,7 @@ public com.commercetools.api.models.product.ProductReference getProduct() {
      * @return oldVariantSelection
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantSelection getOldVariantSelection() {
         return this.oldVariantSelection;
     }
@@ -469,6 +470,7 @@ public com.commercetools.api.models.product_selection.ProductVariantSelection ge
      * @return newVariantSelection
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantSelection getNewVariantSelection() {
         return this.newVariantSelection;
     }
@@ -491,10 +493,6 @@ public ProductSelectionVariantSelectionChangedMessage build() {
         Objects.requireNonNull(resourceVersion,
             ProductSelectionVariantSelectionChangedMessage.class + ": resourceVersion is missing");
         Objects.requireNonNull(product, ProductSelectionVariantSelectionChangedMessage.class + ": product is missing");
-        Objects.requireNonNull(oldVariantSelection,
-            ProductSelectionVariantSelectionChangedMessage.class + ": oldVariantSelection is missing");
-        Objects.requireNonNull(newVariantSelection,
-            ProductSelectionVariantSelectionChangedMessage.class + ": newVariantSelection is missing");
         return new ProductSelectionVariantSelectionChangedMessageImpl(id, version, createdAt, lastModifiedAt,
             lastModifiedBy, createdBy, sequenceNumber, resource, resourceVersion, resourceUserProvidedIdentifiers,
             product, oldVariantSelection, newVariantSelection);
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessagePayload.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessagePayload.java
index 99f69ded85b..76ebfc89ec0 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessagePayload.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessagePayload.java
@@ -26,8 +26,6 @@
  * <pre><code class='java'>
  *     ProductSelectionVariantSelectionChangedMessagePayload productSelectionVariantSelectionChangedMessagePayload = ProductSelectionVariantSelectionChangedMessagePayload.builder()
  *             .product(productBuilder -> productBuilder)
- *             .oldVariantSelection(oldVariantSelectionBuilder -> oldVariantSelectionBuilder)
- *             .newVariantSelection(newVariantSelectionBuilder -> newVariantSelectionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -55,7 +53,6 @@ public interface ProductSelectionVariantSelectionChangedMessagePayload extends M
      *  <p>Product Variant Selection before the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionSetVariantSelectionAction" rel="nofollow">Set Variant Selection</a> update action.</p>
      * @return oldVariantSelection
      */
-    @NotNull
     @Valid
     @JsonProperty("oldVariantSelection")
     public ProductVariantSelection getOldVariantSelection();
@@ -64,7 +61,6 @@ public interface ProductSelectionVariantSelectionChangedMessagePayload extends M
      *  <p>Product Variant Selection after the <a href="https://docs.commercetools.com/apis/ctp:api:type:ProductSelectionSetVariantSelectionAction" rel="nofollow">Set Variant Selection</a> update action.</p>
      * @return newVariantSelection
      */
-    @NotNull
     @Valid
     @JsonProperty("newVariantSelection")
     public ProductVariantSelection getNewVariantSelection();
diff --git a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessagePayloadBuilder.java b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessagePayloadBuilder.java
index 4804efbe6cd..c186e6c02a0 100644
--- a/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessagePayloadBuilder.java
+++ b/commercetools/commercetools-sdk-java-api/src/main/java-generated/com/commercetools/api/models/message/ProductSelectionVariantSelectionChangedMessagePayloadBuilder.java
@@ -4,6 +4,8 @@
 import java.util.*;
 import java.util.function.Function;
 
+import javax.annotation.Nullable;
+
 import io.vrap.rmf.base.client.Builder;
 import io.vrap.rmf.base.client.utils.Generated;
 
@@ -15,8 +17,6 @@
  * <pre><code class='java'>
  *     ProductSelectionVariantSelectionChangedMessagePayload productSelectionVariantSelectionChangedMessagePayload = ProductSelectionVariantSelectionChangedMessagePayload.builder()
  *             .product(productBuilder -> productBuilder)
- *             .oldVariantSelection(oldVariantSelectionBuilder -> oldVariantSelectionBuilder)
- *             .newVariantSelection(newVariantSelectionBuilder -> newVariantSelectionBuilder)
  *             .build()
  * </code></pre>
  * </div>
@@ -27,8 +27,10 @@ public class ProductSelectionVariantSelectionChangedMessagePayloadBuilder
 
     private com.commercetools.api.models.product.ProductReference product;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantSelection oldVariantSelection;
 
+    @Nullable
     private com.commercetools.api.models.product_selection.ProductVariantSelection newVariantSelection;
 
     /**
@@ -74,7 +76,7 @@ public ProductSelectionVariantSelectionChangedMessagePayloadBuilder product(
      */
 
     public ProductSelectionVariantSelectionChangedMessagePayloadBuilder oldVariantSelection(
-            final com.commercetools.api.models.product_selection.ProductVariantSelection oldVariantSelection) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantSelection oldVariantSelection) {
         this.oldVariantSelection = oldVariantSelection;
         return this;
     }
@@ -100,7 +102,7 @@ public ProductSelectionVariantSelectionChangedMessagePayloadBuilder oldVariantSe
      */
 
     public ProductSelectionVariantSelectionChangedMessagePayloadBuilder newVariantSelection(
-            final com.commercetools.api.models.product_selection.ProductVariantSelection newVariantSelection) {
+            @Nullable final com.commercetools.api.models.product_selection.ProductVariantSelection newVariantSelection) {
         this.newVariantSelection = newVariantSelection;
         return this;
     }
@@ -133,6 +135,7 @@ public com.commercetools.api.models.product.ProductReference getProduct() {
      * @return oldVariantSelection
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantSelection getOldVariantSelection() {
         return this.oldVariantSelection;
     }
@@ -142,6 +145,7 @@ public com.commercetools.api.models.product_selection.ProductVariantSelection ge
      * @return newVariantSelection
      */
 
+    @Nullable
     public com.commercetools.api.models.product_selection.ProductVariantSelection getNewVariantSelection() {
         return this.newVariantSelection;
     }
@@ -153,10 +157,6 @@ public com.commercetools.api.models.product_selection.ProductVariantSelection ge
     public ProductSelectionVariantSelectionChangedMessagePayload build() {
         Objects.requireNonNull(product,
             ProductSelectionVariantSelectionChangedMessagePayload.class + ": product is missing");
-        Objects.requireNonNull(oldVariantSelection,
-            ProductSelectionVariantSelectionChangedMessagePayload.class + ": oldVariantSelection is missing");
-        Objects.requireNonNull(newVariantSelection,
-            ProductSelectionVariantSelectionChangedMessagePayload.class + ": newVariantSelection is missing");
         return new ProductSelectionVariantSelectionChangedMessagePayloadImpl(product, oldVariantSelection,
             newVariantSelection);
     }
diff --git a/references.txt b/references.txt
index c977f7ee276..be6c445227a 100644
--- a/references.txt
+++ b/references.txt
@@ -465,3 +465,4 @@ f8b027c8e1b5ba61ace3d3d358b9efc7ad4b93eb
 91ef231b5881c329f1c3f405e250106f8473b57e
 e111bc9d132c5da4dc43085c1983efa8cbdf91d3
 e60554cf51abaeb40bb26716fb27ada4c135b40f
+0ccd9d7c7f9d43d7c437c69ec81c50b0d4ddc641