diff --git a/types/forge-viewer/index.d.ts b/types/forge-viewer/index.d.ts
index 32cd3c8a90..95f81d1b04 100644
--- a/types/forge-viewer/index.d.ts
+++ b/types/forge-viewer/index.d.ts
@@ -353,7 +353,7 @@ declare namespace Autodesk {
         class Document {
             constructor(dataJSON: object, path: string, acmsession: string);
             static load(documentId: string, successCallback: (doc: Document) => void,
-            errorCallback: (errorCode: ErrorCodes, errorMsg: string, messages: any[]) => void, accessControlProperties: any): void;
+            errorCallback: (errorCode: ErrorCodes, errorMsg: string, messages: any[]) => void, accessControlProperties?: any): void;
             static getSubItemsWithProperties(item: object, properties: Properties, recursive: boolean): object[];
 
             acmSessionId: string;
@@ -373,7 +373,7 @@ declare namespace Autodesk {
             getViewableItems(document: Document): void;
             getViewablePath(item: object, outLoadOptions: object): string;
             getViewGeometry(item: object): object;
-            load(documentId: string, onSuccessCallback: () => void, onErrorCallback: () => void, accessControlProperties: object): void;
+            load(documentId: string, onSuccessCallback: () => void, onErrorCallback: () => void, accessControlProperties?: object): void;
             requestThumbnailWithSecurity(data: string, onComplete: (err: Error, response: any) => void): void;
         }