diff --git a/src/typings/index.ts b/src/typings/index.ts
index b53e375..dec0c93 100644
--- a/src/typings/index.ts
+++ b/src/typings/index.ts
@@ -67,7 +67,7 @@ export interface FeedOptions {
   description?: string;
   image?: string;
   favicon?: string;
-  copyright: string;
+  copyright?: string;
 }
 
 export interface Extension {