diff --git a/include/ruby/backward.h b/include/ruby/backward.h
index 84abba2dab..d8ea12b8dd 100644
--- a/include/ruby/backward.h
+++ b/include/ruby/backward.h
@@ -8,19 +8,10 @@
  *             modify this file, provided that  the conditions mentioned in the
  *             file COPYING are met.  Consult the file for details.
  */
-#include "ruby/internal/core/rbasic.h"
 #include "ruby/internal/value.h"
 #include "ruby/internal/interpreter.h"
 #include "ruby/backward/2/attributes.h"
 
-#define RClass RClassDeprecated
-#ifndef __cplusplus
-DEPRECATED_TYPE(("RClass is internal use only"),
-struct RClass {
-    struct RBasic basic;
-});
-#endif
-
 #define DECLARE_DEPRECATED_FEATURE(ver, func) \
     NORETURN(ERRORFUNC(("deprecated since "#ver), DEPRECATED(void func(void))))
 
diff --git a/internal/class.h b/internal/class.h
index 816a3044f4..bb12825162 100644
--- a/internal/class.h
+++ b/internal/class.h
@@ -16,10 +16,6 @@
 #include "ruby/intern.h"        /* for rb_alloc_func_t */
 #include "ruby/ruby.h"          /* for struct RBasic */
 
-#ifdef RClass
-# undef RClass /* See also include/ruby/backward.h */
-#endif
-
 #ifdef RCLASS_SUPER
 # undef RCLASS_SUPER
 #endif