diff --git a/docs/api/cases/cases-api-create.asciidoc b/docs/api/cases/cases-api-create.asciidoc
index 2cf69630a82c4..03abab4dac1b0 100644
--- a/docs/api/cases/cases-api-create.asciidoc
+++ b/docs/api/cases/cases-api-create.asciidoc
@@ -28,6 +28,18 @@ default space is used.
 [role="child_attributes"]
 === {api-request-body-title}
 
+`assignees`::
+(Optional, array of objects) Array containing users that are assigned to the case.
++
+.Properties of assignee objects
+[%collapsible%open]
+=====
+`uid`:: 
+(Required, string) A unique identifier for the user profile. These identifiers
+can be found by using the
+{ref}/security-api-suggest-user-profile.html[suggest user profile API].
+=====
+
 `connector`::
 (Required, object) An object that contains the connector configuration.
 +
@@ -201,6 +213,7 @@ the case identifier, version, and creation time. For example:
   "totalAlerts": 0,
   "title": "Case title 1",
   "tags": [ "tag 1" ],
+  "assignees": [],
   "settings": {
     "syncAlerts": true
   },
diff --git a/docs/api/cases/cases-api-find-cases.asciidoc b/docs/api/cases/cases-api-find-cases.asciidoc
index d7ae5fed35b0f..770e1d30ee594 100644
--- a/docs/api/cases/cases-api-find-cases.asciidoc
+++ b/docs/api/cases/cases-api-find-cases.asciidoc
@@ -141,6 +141,7 @@ The API returns a JSON object listing the retrieved cases. For example:
         "full_name": "Joe Smith",
         "username": "jsmith"
       },
+      "assignees": [],
       "connector": {
         "id": "none",
         "name": "none",
diff --git a/docs/api/cases/cases-api-get-case.asciidoc b/docs/api/cases/cases-api-get-case.asciidoc
index d7bc316a7346d..9d43afb695a79 100644
--- a/docs/api/cases/cases-api-get-case.asciidoc
+++ b/docs/api/cases/cases-api-get-case.asciidoc
@@ -86,6 +86,7 @@ The API returns a JSON object with the retrieved case. For example:
   "status":"open",
   "updated_at":"2022-07-13T15:40:32.335Z",
   "updated_by":{"full_name":null,"email":null,"username":"elastic"},
+  "assignees":[{"uid":"u_mGBROF_q5bmFCATbLXAcCwKa0k8JvONAwSruelyKA5E_0"}],
   "connector":{"id":"none","name":"none","type":".none","fields":null},
   "external_service":null
 }
diff --git a/docs/api/cases/cases-api-update.asciidoc b/docs/api/cases/cases-api-update.asciidoc
index f7ffcdfc8490f..ac7bc29856c7b 100644
--- a/docs/api/cases/cases-api-update.asciidoc
+++ b/docs/api/cases/cases-api-update.asciidoc
@@ -34,6 +34,19 @@ default space is used.
 .Properties of `cases` objects
 [%collapsible%open]
 ====
+
+`assignees`::
+(Optional, array of objects) Array containing users that are assigned to the case.
++
+.Properties of assignee objects
+[%collapsible%open]
+=====
+`uid`::
+(Required, string) A unique identifier for the user profile. These identifiers
+can be found by using the
+{ref}/security-api-suggest-user-profile.html[suggest user profile API].
+=====
+
 `connector`::
 (Optional, object) An object that contains the connector configuration.
 +
@@ -197,6 +210,7 @@ PATCH api/cases
       },
       "description": "A new description.",
       "tags": [ "tag-1", "tag-2" ],
+      "assignees": [],
       "settings": {
         "syncAlerts": true
       }
diff --git a/x-pack/plugins/cases/docs/openapi/components/examples/create_case_response.yaml b/x-pack/plugins/cases/docs/openapi/components/examples/create_case_response.yaml
index 7d9cdf3626c72..8cd80595abf30 100644
--- a/x-pack/plugins/cases/docs/openapi/components/examples/create_case_response.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/examples/create_case_response.yaml
@@ -8,6 +8,7 @@ value:
   title: Case title 1
   tags:
     - tag 1
+  assignees: []
   description: A case description.
   settings:
     syncAlerts: false
diff --git a/x-pack/plugins/cases/docs/openapi/components/examples/find_case_response.yaml b/x-pack/plugins/cases/docs/openapi/components/examples/find_case_response.yaml
index 1c8168dde7708..6f744d03a1365 100644
--- a/x-pack/plugins/cases/docs/openapi/components/examples/find_case_response.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/examples/find_case_response.yaml
@@ -33,6 +33,7 @@ value:
           "full_name": null,
           "username": "elastic"
         },
+        "assignees": [],
         "connector": {
           "id": "none",
           "name": "none",
diff --git a/x-pack/plugins/cases/docs/openapi/components/examples/get_case_response.yaml b/x-pack/plugins/cases/docs/openapi/components/examples/get_case_response.yaml
index 936a21a5cfc70..bd74fa423bb9c 100644
--- a/x-pack/plugins/cases/docs/openapi/components/examples/get_case_response.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/examples/get_case_response.yaml
@@ -34,7 +34,9 @@ value:
     "created_at":"2022-07-13T15:33:50.604Z",
     "created_by":{"username":"elastic","email":null,"full_name":null},"status":"open",
     "updated_at":"2022-07-13T15:40:32.335Z",
-    "updated_by":{"full_name":null,"email":null,"username":"elastic"},"connector":{
+    "updated_by":{"full_name":null,"email":null,"username":"elastic"},
+    "assignees":[{"uid":"u_mGBROF_q5bmFCATbLXAcCwKa0k8JvONAwSruelyKA5E_0"}],
+    "connector":{
       "id":"none",
       "name":"none",
       "type":".none",
diff --git a/x-pack/plugins/cases/docs/openapi/components/examples/update_case_response.yaml b/x-pack/plugins/cases/docs/openapi/components/examples/update_case_response.yaml
index 7413547e6ff60..eaf421771b51e 100644
--- a/x-pack/plugins/cases/docs/openapi/components/examples/update_case_response.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/examples/update_case_response.yaml
@@ -31,6 +31,7 @@ value:
         "full_name": null,
         "username": "elastic"
       },
+      "assignees": [],
       "connector": {
         "id": "131d4448-abe0-4789-939d-8ef60680b498",
         "name": "My connector",
diff --git a/x-pack/plugins/cases/docs/openapi/components/schemas/action_types.yaml b/x-pack/plugins/cases/docs/openapi/components/schemas/action_types.yaml
index 05e3fc6ab04b7..3568008b07000 100644
--- a/x-pack/plugins/cases/docs/openapi/components/schemas/action_types.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/schemas/action_types.yaml
@@ -1,6 +1,7 @@
 type: string
 description: The type of action.
 enum:
+  - assignees
   - create_case
   - comment
   - connector
diff --git a/x-pack/plugins/cases/docs/openapi/components/schemas/case_response_properties.yaml b/x-pack/plugins/cases/docs/openapi/components/schemas/case_response_properties.yaml
index a53d88f3be69b..1caa1643476d5 100644
--- a/x-pack/plugins/cases/docs/openapi/components/schemas/case_response_properties.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/schemas/case_response_properties.yaml
@@ -22,7 +22,20 @@ required:
   - updated_at
   - updated_by
   - version
-properties: 
+properties:
+  assignees:
+    type: array
+    description: An array containing users that are assigned to the case.
+    nullable: true
+    items:
+      type: object
+      required:
+        - uid
+      properties:
+        uid:
+          type: string
+          description: A unique identifier for the user profile. You can use the get user profile API to retrieve more details.
+          example: u_0wpfV1MqYDaXzLtRVY-gLMrddKDEmfz51Fszhj7hWC8_0
   closed_at:
     type: string
     format: date-time
diff --git a/x-pack/plugins/cases/docs/openapi/components/schemas/create_case_request.yaml b/x-pack/plugins/cases/docs/openapi/components/schemas/create_case_request.yaml
index ab6b49c653668..715bfaf112042 100644
--- a/x-pack/plugins/cases/docs/openapi/components/schemas/create_case_request.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/schemas/create_case_request.yaml
@@ -10,6 +10,19 @@ required:
       - tags
       - title
 properties:
+  assignees:
+    type: array
+    description: An array containing users that are assigned to the case.
+    nullable: true
+    items:
+      type: object
+      required:
+        - uid
+      properties:
+        uid:
+          type: string
+          description: A unique identifier for the user profile. These identifiers can be found by using the suggest user profile API.
+          example: u_0wpfV1MqYDaXzLtRVY-gLMrddKDEmfz51Fszhj7hWC8_0
   connector:
     oneOf:
       - $ref: 'connector_properties_none.yaml'
diff --git a/x-pack/plugins/cases/docs/openapi/components/schemas/payload_assignees.yaml b/x-pack/plugins/cases/docs/openapi/components/schemas/payload_assignees.yaml
new file mode 100644
index 0000000000000..122541dfe4fe6
--- /dev/null
+++ b/x-pack/plugins/cases/docs/openapi/components/schemas/payload_assignees.yaml
@@ -0,0 +1,9 @@
+type: object
+properties:
+  assignees:
+    type: array
+    items:
+      type: object
+      properties:
+        uid:
+          type: string
\ No newline at end of file
diff --git a/x-pack/plugins/cases/docs/openapi/components/schemas/update_case_request.yaml b/x-pack/plugins/cases/docs/openapi/components/schemas/update_case_request.yaml
index f6feac43b1613..ee4249aeaf9d3 100644
--- a/x-pack/plugins/cases/docs/openapi/components/schemas/update_case_request.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/schemas/update_case_request.yaml
@@ -13,7 +13,20 @@ properties:
       required:
         - id
         - version
-      properties: 
+      properties:
+        assignees:
+          type: array
+          description: An array containing users that are assigned to the case.
+          nullable: true
+          items:
+            type: object
+            required:
+             - uid
+            properties:
+              uid:
+                type: string
+                description: A unique identifier for the user profile. These identifiers can be found by using the suggest user profile API.
+                example: u_0wpfV1MqYDaXzLtRVY-gLMrddKDEmfz51Fszhj7hWC8_0
         connector:
           oneOf:
             - $ref: 'connector_properties_none.yaml'
diff --git a/x-pack/plugins/cases/docs/openapi/components/schemas/user_actions_response_properties.yaml b/x-pack/plugins/cases/docs/openapi/components/schemas/user_actions_response_properties.yaml
index e828f3441cb5d..a3f57ed53297d 100644
--- a/x-pack/plugins/cases/docs/openapi/components/schemas/user_actions_response_properties.yaml
+++ b/x-pack/plugins/cases/docs/openapi/components/schemas/user_actions_response_properties.yaml
@@ -24,6 +24,7 @@ properties:
   payload:
     oneOf:
       - $ref: 'payload_alert_comment.yaml'
+      - $ref: 'payload_assignees.yaml'
       - $ref: 'payload_connector.yaml'
       - $ref: 'payload_create_case.yaml'
       - $ref: 'payload_description.yaml'