diff --git a/docs/Model/Filter.md b/docs/Model/Filter.md
index 8b0764d..4babae6 100644
--- a/docs/Model/Filter.md
+++ b/docs/Model/Filter.md
@@ -6,7 +6,7 @@ Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
 **field** | **string** | Required. Name of the field to use as the first operand in the filter expression. | [optional]
 **key** | **string** | If `field` is `tag`, this field is *required* to specify `key` inside the tags. | [optional]
-**value** | **string** | Constant value to use as the second operand in the filter expression. This value is *required* when the relation operator is a binary operator. | [optional]
+**value** | **string** | Constant value to use as the second operand in the filter expression. This value is *required* when the relation operator is a binary operator. For `in_array` and `not_in_array` relations, provide a comma-separated list of up to 20 values. | [optional]
 **hours_ago** | **string** | If `field` is session-related, this is *required* to specify the number of hours before or after the user's session. | [optional]
 **radius** | **float** | If `field` is `location`, this will specify the radius in meters from a provided location point. Use with `lat` and `long`. | [optional]
 **lat** | **float** | If `field` is `location`, this is *required* to specify the user's latitude. | [optional]
diff --git a/docs/Model/FilterExpression.md b/docs/Model/FilterExpression.md
index 0284236..3cbb744 100644
--- a/docs/Model/FilterExpression.md
+++ b/docs/Model/FilterExpression.md
@@ -6,7 +6,7 @@ Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
 **field** | **string** | Required. Name of the field to use as the first operand in the filter expression. | [optional]
 **key** | **string** | If `field` is `tag`, this field is *required* to specify `key` inside the tags. | [optional]
-**value** | **string** | Constant value to use as the second operand in the filter expression. This value is *required* when the relation operator is a binary operator. | [optional]
+**value** | **string** | Constant value to use as the second operand in the filter expression. This value is *required* when the relation operator is a binary operator. For `in_array` and `not_in_array` relations, provide a comma-separated list of up to 20 values. | [optional]
 **hours_ago** | **string** | If `field` is session-related, this is *required* to specify the number of hours before or after the user's session. | [optional]
 **radius** | **float** | If `field` is `location`, this will specify the radius in meters from a provided location point. Use with `lat` and `long`. | [optional]
 **lat** | **float** | If `field` is `location`, this is *required* to specify the user's latitude. | [optional]
diff --git a/lib/model/Filter.php b/lib/model/Filter.php
index 3693af9..1566649 100644
--- a/lib/model/Filter.php
+++ b/lib/model/Filter.php
@@ -206,6 +206,8 @@ public function getModelName()
     public const RELATION_NOT_EXISTS = 'not_exists';
     public const RELATION_TIME_ELAPSED_GT = 'time_elapsed_gt';
     public const RELATION_TIME_ELAPSED_LT = 'time_elapsed_lt';
+    public const RELATION_IN_ARRAY = 'in_array';
+    public const RELATION_NOT_IN_ARRAY = 'not_in_array';
 
     /**
      * Gets allowable values of the enum
@@ -223,6 +225,8 @@ public function getRelationAllowableValues()
             self::RELATION_NOT_EXISTS,
             self::RELATION_TIME_ELAPSED_GT,
             self::RELATION_TIME_ELAPSED_LT,
+            self::RELATION_IN_ARRAY,
+            self::RELATION_NOT_IN_ARRAY,
         ];
     }
 
@@ -345,7 +349,7 @@ public function getValue()
     /**
      * Sets value
      *
-     * @param string|null $value Constant value to use as the second operand in the filter expression. This value is *required* when the relation operator is a binary operator.
+     * @param string|null $value Constant value to use as the second operand in the filter expression. This value is *required* when the relation operator is a binary operator. For `in_array` and `not_in_array` relations, provide a comma-separated list of up to 20 values.
      *
      * @return self
      */
diff --git a/lib/model/FilterExpression.php b/lib/model/FilterExpression.php
index ecc01d9..460197b 100644
--- a/lib/model/FilterExpression.php
+++ b/lib/model/FilterExpression.php
@@ -211,6 +211,8 @@ public function getModelName()
     public const RELATION_NOT_EXISTS = 'not_exists';
     public const RELATION_TIME_ELAPSED_GT = 'time_elapsed_gt';
     public const RELATION_TIME_ELAPSED_LT = 'time_elapsed_lt';
+    public const RELATION_IN_ARRAY = 'in_array';
+    public const RELATION_NOT_IN_ARRAY = 'not_in_array';
     public const OPERATOR__OR = 'OR';
     public const OPERATOR__AND = 'AND';
 
@@ -230,6 +232,8 @@ public function getRelationAllowableValues()
             self::RELATION_NOT_EXISTS,
             self::RELATION_TIME_ELAPSED_GT,
             self::RELATION_TIME_ELAPSED_LT,
+            self::RELATION_IN_ARRAY,
+            self::RELATION_NOT_IN_ARRAY,
         ];
     }
 
@@ -375,7 +379,7 @@ public function getValue()
     /**
      * Sets value
      *
-     * @param string|null $value Constant value to use as the second operand in the filter expression. This value is *required* when the relation operator is a binary operator.
+     * @param string|null $value Constant value to use as the second operand in the filter expression. This value is *required* when the relation operator is a binary operator. For `in_array` and `not_in_array` relations, provide a comma-separated list of up to 20 values.
      *
      * @return self
      */