diff --git a/dlls/ext-ms-win-ntuser-private-l1-1-1/ext-ms-win-ntuser-private-l1-1-1.spec b/dlls/ext-ms-win-ntuser-private-l1-1-1/ext-ms-win-ntuser-private-l1-1-1.spec
index 958837ba2fc..d75425c9ef5 100644
--- a/dlls/ext-ms-win-ntuser-private-l1-1-1/ext-ms-win-ntuser-private-l1-1-1.spec
+++ b/dlls/ext-ms-win-ntuser-private-l1-1-1/ext-ms-win-ntuser-private-l1-1-1.spec
@@ -15,7 +15,7 @@
 @ stub RecordShutdownReason
 @ stdcall RegisterLogonProcess(long long) user32.RegisterLogonProcess
 @ stub SetThreadInputBlocked
-@ stub SetWindowCompositionAttribute
+@ stdcall SetWindowCompositionAttribute(ptr ptr) user32.SetWindowCompositionAttribute
 @ stdcall SetWindowStationUser(long long) user32.SetWindowStationUser
 @ stub SwitchDesktopWithFade
 @ stub UnlockWindowStation
diff --git a/dlls/user32/user32.spec b/dlls/user32/user32.spec
index 61e0e4e8cc3..a340e02adce 100644
--- a/dlls/user32/user32.spec
+++ b/dlls/user32/user32.spec
@@ -711,6 +711,7 @@
 @ stdcall SetUserObjectInformationW(long long ptr long)
 @ stdcall SetUserObjectSecurity(long ptr ptr)
 @ stdcall SetWinEventHook(long long long ptr long long long)
+@ stdcall SetWindowCompositionAttribute(ptr ptr)
 @ stdcall SetWindowContextHelpId(long long)
 @ stdcall SetWindowDisplayAffinity(long long)
 @ stub SetWindowFullScreenState
diff --git a/dlls/user32/win.c b/dlls/user32/win.c
index 2a55ab4ce67..95f5ac73c88 100644
--- a/dlls/user32/win.c
+++ b/dlls/user32/win.c
@@ -4183,3 +4183,13 @@ BOOL WINAPI SetWindowDisplayAffinity(HWND hwnd, DWORD affinity)
     SetLastError(ERROR_NOT_ENOUGH_MEMORY);
     return FALSE;
 }
+
+/**********************************************************************
+ *              SetWindowCompositionAttribute (USER32.@)
+ */
+BOOL WINAPI SetWindowCompositionAttribute(HWND hwnd, void *data)
+{
+    FIXME("(%p, %p): stub\n", hwnd, data);
+    SetLastError(ERROR_CALL_NOT_IMPLEMENTED);
+    return FALSE;
+}