diff --git a/types/sinon/index.d.ts b/types/sinon/index.d.ts
index 27bc691d3a..4c8f22a6f4 100644
--- a/types/sinon/index.d.ts
+++ b/types/sinon/index.d.ts
@@ -1,4 +1,4 @@
-// Type definitions for Sinon 2.3
+// Type definitions for Sinon 4.0
 // Project: http://sinonjs.org/
 // Definitions by: William Sears <https://github.com/mrbigdog2u>
 //                 Jonathan Little <https://github.com/rationull>