diff --git a/windows/src/Key/ClientKeyRouter.h b/windows/src/Key/ClientKeyRouter.h
deleted file mode 100644
index 5af16e91..00000000
--- a/windows/src/Key/ClientKeyRouter.h
+++ /dev/null
@@ -1,25 +0,0 @@
-#pragma once
-
-#include <cstdint>
-
-struct ClientFocusLease {
-    uint64_t client = 0;
-    uint64_t epoch = 0;
-    uint64_t token = 0;
-};
-
-struct ClientKeyEvent {
-    ClientFocusLease lease;
-    uint32_t virtual_key = 0;
-    uint32_t scan_code = 0;
-    uint32_t modifiers = 0;
-    char16_t character = 0;
-    bool ui_less = false;
-};
-
-class IClientKeyRouter {
-  public:
-    virtual ~IClientKeyRouter() = default;
-    virtual bool dispatch(const ClientKeyEvent &event) = 0;
-    virtual bool cancel(const ClientFocusLease &lease) = 0;
-};
diff --git a/windows/src/Key/KeyStateCategory.h b/windows/src/Key/KeyStateCategory.h
index 222e9213..66645d8c 100644
--- a/windows/src/Key/KeyStateCategory.h
+++ b/windows/src/Key/KeyStateCategory.h
@@ -2,7 +2,6 @@
 #include "Globals.h"
 #include "Private.h"
 #include "MetasequoiaIME.h"
-#include "ClientKeyRouter.h"
 #include <cstdint>
 #include <string>
 
@@ -47,13 +46,6 @@ typedef struct KeyHandlerEditSessionDTO
     std::wstring prefetchedText;
 } KeyHandlerEditSessionDTO;
 
-inline ClientKeyEvent client_key_event(const KeyHandlerEditSessionDTO &dto,
-                                       ClientFocusLease lease,
-                                       uint32_t modifiers = 0,
-                                       bool ui_less = false) {
-    return {lease, dto.code, 0, modifiers, static_cast<char16_t>(dto.wch), ui_less};
-}
-
 class CKeyStateCategory
 {
   public: