diff --git a/src/Model/Category/CategoryDraft.php b/src/Model/Category/CategoryDraft.php
index a1b85832af..ad64afa0ea 100644
--- a/src/Model/Category/CategoryDraft.php
+++ b/src/Model/Category/CategoryDraft.php
@@ -28,6 +28,12 @@
  * @method CategoryDraft setExternalId(string $externalId = null)
  * @method CustomFieldObjectDraft getCustom()
  * @method CategoryDraft setCustom(CustomFieldObjectDraft $custom = null)
+ * @method LocalizedString getMetaDescription()
+ * @method CategoryDraft setMetaDescription(LocalizedString $metaDescription = null)
+ * @method LocalizedString getMetaTitle()
+ * @method CategoryDraft setMetaTitle(LocalizedString $metaTitle = null)
+ * @method LocalizedString getMetaKeywords()
+ * @method CategoryDraft setMetaKeywords(LocalizedString $metaKeywords = null)
  */
 class CategoryDraft extends JsonObject
 {
diff --git a/src/Model/Common/AbstractJsonDeserializeObject.php b/src/Model/Common/AbstractJsonDeserializeObject.php
index 7ebc92e7a2..35092fa1a9 100644
--- a/src/Model/Common/AbstractJsonDeserializeObject.php
+++ b/src/Model/Common/AbstractJsonDeserializeObject.php
@@ -29,7 +29,7 @@ public function __construct(array $data = [], $context = null)
     {
         $this->setContext($context);
         if (!is_null($data)) {
-            $this->rawData = $data;
+            $this->rawData = $this->typeData = $data;
         }
     }
 
@@ -158,7 +158,7 @@ protected function getTyped($offset)
      */
     public function setRawData(array $rawData)
     {
-        $this->rawData = $rawData;
+        $this->rawData = $this->typeData = $rawData;
 
         return $this;
     }
@@ -190,8 +190,7 @@ public function jsonSerialize()
      */
     public function toArray()
     {
-        $data = array_merge($this->rawData, $this->typeData);
-        $data = array_filter($data, function ($value) {
+        $data = array_filter($this->typeData, function ($value) {
             return !is_null($value);
         });
         $data = array_map(
diff --git a/src/Model/Common/Collection.php b/src/Model/Common/Collection.php
index 6f9bd5a5dc..b938fbf1c7 100644
--- a/src/Model/Common/Collection.php
+++ b/src/Model/Common/Collection.php
@@ -142,7 +142,7 @@ protected function initialize($offset)
      */
     public function toArray()
     {
-        $values = $this->rawData;
+        $values = [];
         foreach ($this->typeData as $key => $value) {
             if ($value instanceof JsonDeserializeInterface) {
                 $values[$key] = $value->toArray();
diff --git a/tests/unit/Model/Common/CollectionTest.php b/tests/unit/Model/Common/CollectionTest.php
index f20fe87acd..7259b9fd99 100644
--- a/tests/unit/Model/Common/CollectionTest.php
+++ b/tests/unit/Model/Common/CollectionTest.php
@@ -213,7 +213,7 @@ public function testGetReturnRaw()
             [[new \DateTime('2015-01-01')]]
         );
         $collection->setType('\DateTime');
-        $this->assertSame('2015-01-01', $collection->getAt(0)->format('Y-m-d'));
+        $this->assertSame('2015-01-01', $collection->current()->format('Y-m-d'));
     }
 
     public function testSetAt()
@@ -224,4 +224,15 @@ public function testSetAt()
 
         $this->assertInstanceOf('\DateTime', $collection[1]);
     }
+
+    public function testAdd()
+    {
+        $collection = Collection::fromArray([
+            ['currencyCode' => 'EUR', 'centAmount' => 100],
+        ]);
+        $collection->setType('\Commercetools\Core\Model\Common\Money');
+        $collection->add(Money::ofCurrencyAndAmount('USD', 110));
+
+        $this->assertCount(2, $collection);
+    }
 }