diff --git a/types/gapi.client.calendar/gapi.client.calendar-tests.ts b/types/gapi.client.calendar/gapi.client.calendar-tests.ts
index a3f59d0612..460f31a769 100644
--- a/types/gapi.client.calendar/gapi.client.calendar-tests.ts
+++ b/types/gapi.client.calendar/gapi.client.calendar-tests.ts
@@ -4,7 +4,7 @@
 * In case of any problems please post issue to https://github.com/Maxim-Mazurok/google-api-typings-generator
 **/
 
-// Revision: 20200902
+// Revision: 20200917
 
 gapi.load('client', () => {
     /** now we can use gapi.client */
diff --git a/types/gapi.client.calendar/index.d.ts b/types/gapi.client.calendar/index.d.ts
index af97762702..b9bba2c78f 100644
--- a/types/gapi.client.calendar/index.d.ts
+++ b/types/gapi.client.calendar/index.d.ts
@@ -11,7 +11,7 @@
 // This file was generated by https://github.com/Maxim-Mazurok/google-api-typings-generator. Please do not edit it manually.
 // In case of any problems please post issue to https://github.com/Maxim-Mazurok/google-api-typings-generator
 // Generated from: https://www.googleapis.com/discovery/v1/apis/calendar/v3/rest
-// Revision: 20200902
+// Revision: 20200917
 
 /// <reference types="gapi.client" />
 
@@ -405,7 +405,10 @@ declare namespace gapi.client {
              * There can be at most 25 attachments per event,
              */
             attachments?: EventAttachment[];
-            /** The attendees of the event. See the Events with attendees guide for more information on scheduling events with other calendar users. */
+            /**
+             * The attendees of the event. See the Events with attendees guide for more information on scheduling events with other calendar users. Service accounts need to use domain-wide
+             * delegation of authority to populate the attendee list.
+             */
             attendees?: EventAttendee[];
             /**
              * Whether attendees may have been omitted from the event's representation. When retrieving an event, this may be due to a restriction specified by the maxAttendee query parameter.