diff --git a/ompi/mpi/c/win_allocate.c.in b/ompi/mpi/c/win_allocate.c.in
index b1f40905b11..006ffd218d5 100644
--- a/ompi/mpi/c/win_allocate.c.in
+++ b/ompi/mpi/c/win_allocate.c.in
@@ -13,7 +13,7 @@
  * Copyright (c) 2015      Research Organization for Information Science
  *                         and Technology (RIST). All rights reserved.
  * Copyright (c) 2017      IBM Corporation. All rights reserved.
- * Copyright (c) 2024      Triad National Security, LLC. All rights
+ * Copyright (c) 2024-2025 Triad National Security, LLC. All rights
  *                         reserved.
  * $COPYRIGHT$
  *
@@ -67,22 +67,8 @@ PROTOTYPE ERROR_CLASS win_allocate(AINT size, DISP disp_unit, INFO info,
         return OMPI_ERRHANDLER_INVOKE(comm, MPI_ERR_COMM, FUNC_NAME);
     }
 
-/*
- * TODO:BIGCOUNT remove this check once ompi-rma supports bigcount
- */
-#if OMPI_BIGCOUNT_SRC
-    OMPI_CHECK_MPI_COUNT_INT_CONVERSION_OVERFLOW(ret, disp_unit);
-    if (OMPI_SUCCESS != ret) {
-        *win = MPI_WIN_NULL;
-        return OMPI_ERRHANDLER_INVOKE(comm, ret, FUNC_NAME);
-    }
-#endif
-
     /* create window and return */
-/*
- * TODO:BIGCOUNT remove (int) before disp_unit  once ompi-rma supports bigcount
- */
-    ret = ompi_win_allocate((size_t)size, (int)disp_unit, &(info->super),
+    ret = ompi_win_allocate((size_t)size, (ptrdiff_t)disp_unit, &(info->super),
                             comm, baseptr, win);
     if (OMPI_SUCCESS != ret) {
         *win = MPI_WIN_NULL;
diff --git a/ompi/mpi/c/win_allocate_shared.c.in b/ompi/mpi/c/win_allocate_shared.c.in
index bcec8b3a761..655babad2d2 100644
--- a/ompi/mpi/c/win_allocate_shared.c.in
+++ b/ompi/mpi/c/win_allocate_shared.c.in
@@ -16,7 +16,7 @@
  * Copyright (c) 2015      Research Organization for Information Science
  *                         and Technology (RIST). All rights reserved.
  * Copyright (c) 2017      IBM Corporation. All rights reserved.
- * Copyright (c) 2024      Triad National Security, LLC. All rights
+ * Copyright (c) 2024-2025 Triad National Security, LLC. All rights
  *                         reserved.
  * $COPYRIGHT$
  *
@@ -61,16 +61,6 @@ PROTOTYPE ERROR_CLASS win_allocate_shared(AINT size, DISP disp_unit, INFO info,
         } else if ( size < 0 ) {
             return OMPI_ERRHANDLER_INVOKE(comm, MPI_ERR_SIZE, FUNC_NAME);
         }
-/*
- * TODO:BIGCOUNT remove this check once ompi-rma supports bigcount
- */
-#if OMPI_BIGCOUNT_SRC
-        OMPI_CHECK_MPI_COUNT_INT_CONVERSION_OVERFLOW(ret, disp_unit);
-        if (OMPI_SUCCESS != ret) {
-            *win = MPI_WIN_NULL;
-            return OMPI_ERRHANDLER_INVOKE(comm, ret, FUNC_NAME);
-        }
-#endif
     }
 
     /* communicator must be an intracommunicator */
@@ -79,10 +69,7 @@ PROTOTYPE ERROR_CLASS win_allocate_shared(AINT size, DISP disp_unit, INFO info,
     }
 
     /* create window and return */
-/*
- * TODO:BIGCOUNT remove (int) from disp_unit once ompi-rma supports bigcount
- */
-    ret = ompi_win_allocate_shared((size_t)size, (int)disp_unit, &(info->super),
+    ret = ompi_win_allocate_shared((size_t)size, (ptrdiff_t)disp_unit, &(info->super),
                                    comm, baseptr, win);
     if (OMPI_SUCCESS != ret) {
         *win = MPI_WIN_NULL;
diff --git a/ompi/mpi/c/win_create.c.in b/ompi/mpi/c/win_create.c.in
index c737d22370f..0b1be1a8a24 100644
--- a/ompi/mpi/c/win_create.c.in
+++ b/ompi/mpi/c/win_create.c.in
@@ -13,7 +13,7 @@
  * Copyright (c) 2015      Research Organization for Information Science
  *                         and Technology (RIST). All rights reserved.
  * Copyright (c) 2017      IBM Corporation. All rights reserved.
- * Copyright (c) 2024      Triad National Security, LLC. All rights
+ * Copyright (c) 2024-2025 Triad National Security, LLC. All rights
  *                         reserved.
  * $COPYRIGHT$
  *
@@ -60,16 +60,6 @@ PROTOTYPE ERROR_CLASS win_create(BUFFER_OUT base, AINT size, DISP disp_unit,
         } else if ( disp_unit <= 0 ) {
             return OMPI_ERRHANDLER_INVOKE(comm, MPI_ERR_DISP, FUNC_NAME);
         }
-/*
- * TODO:BIGCOUNT remove this check once ompi-rma supports bigcount
- */
-#if OMPI_BIGCOUNT_SRC
-        OMPI_CHECK_MPI_COUNT_INT_CONVERSION_OVERFLOW(ret, disp_unit);
-        if (OMPI_SUCCESS != ret) {
-            *win = MPI_WIN_NULL;
-            return OMPI_ERRHANDLER_INVOKE(comm, ret, FUNC_NAME);
-        }
-#endif
     }
 
     /* communicator must be an intracommunicator */
@@ -77,11 +67,8 @@ PROTOTYPE ERROR_CLASS win_create(BUFFER_OUT base, AINT size, DISP disp_unit,
         return OMPI_ERRHANDLER_INVOKE(comm, MPI_ERR_COMM, FUNC_NAME);
     }
 
-/*
- * TODO:BIGCOUNT remove (int) before disp_unit once ompi-rma supports bigcount
- */
     /* create window and return */
-    ret = ompi_win_create(base, (size_t)size, (int)disp_unit, comm,
+    ret = ompi_win_create(base, (size_t)size, (ptrdiff_t)disp_unit, comm,
                           &(info->super), win);
     if (OMPI_SUCCESS != ret) {
         *win = MPI_WIN_NULL;
diff --git a/ompi/win/win.c b/ompi/win/win.c
index 87556a44c24..8b29e88b857 100644
--- a/ompi/win/win.c
+++ b/ompi/win/win.c
@@ -17,7 +17,7 @@
  * Copyright (c) 2015-2017 Research Organization for Information Science
  *                         and Technology (RIST). All rights reserved.
  * Copyright (c) 2016-2017 IBM Corporation. All rights reserved.
- * Copyright (c) 2018-2019 Triad National Security, LLC. All rights
+ * Copyright (c) 2018-2025 Triad National Security, LLC. All rights
  *                         reserved.
  * Copyright (c) 2024      Advanced Micro Devices, Inc. All rights reserved.
  * $COPYRIGHT$
@@ -206,7 +206,7 @@ static int alloc_window(struct ompi_communicator_t *comm, opal_info_t *info, int
 }
 
 static int
-config_window(void *base, size_t size, int disp_unit,
+config_window(void *base, size_t size, ptrdiff_t disp_unit,
               int flavor, int model, ompi_win_t *win)
 {
     int ret;
@@ -220,9 +220,15 @@ config_window(void *base, size_t size, int disp_unit,
                              MPI_WIN_SIZE, size, true);
     if (OMPI_SUCCESS != ret) return ret;
 
+    /* 
+     * No this isn't really right but the MPI Forum RMA WG was spleeping during
+     * Big count proposal reading and didn't put in something for Table 12.1 of the 
+     * MPI 5.0 standard for embiggened disp_unit, so here we go with int * in accordance
+     * with that table.
+     */
     ret = ompi_attr_set_int(WIN_ATTR, win,
                             &win->w_keyhash,
-                            MPI_WIN_DISP_UNIT, disp_unit,
+                            MPI_WIN_DISP_UNIT, (int)disp_unit,
                             true);
     if (OMPI_SUCCESS != ret) return ret;
 
@@ -244,7 +250,7 @@ config_window(void *base, size_t size, int disp_unit,
 
 int
 ompi_win_create(void *base, size_t size,
-                int disp_unit, ompi_communicator_t *comm,
+                ptrdiff_t disp_unit, ompi_communicator_t *comm,
                 opal_info_t *info,
                 ompi_win_t** newwin)
 {
@@ -275,7 +281,7 @@ ompi_win_create(void *base, size_t size,
 }
 
 int
-ompi_win_allocate(size_t size, int disp_unit, opal_info_t *info,
+ompi_win_allocate(size_t size, ptrdiff_t disp_unit, opal_info_t *info,
                   ompi_communicator_t *comm, void *baseptr, ompi_win_t **newwin)
 {
     ompi_win_t *win;
@@ -307,7 +313,7 @@ ompi_win_allocate(size_t size, int disp_unit, opal_info_t *info,
 }
 
 int
-ompi_win_allocate_shared(size_t size, int disp_unit, opal_info_t *info,
+ompi_win_allocate_shared(size_t size, ptrdiff_t disp_unit, opal_info_t *info,
                          ompi_communicator_t *comm, void *baseptr, ompi_win_t **newwin)
 {
     ompi_win_t *win;
diff --git a/ompi/win/win.h b/ompi/win/win.h
index a4f48246cc4..ebffd848e47 100644
--- a/ompi/win/win.h
+++ b/ompi/win/win.h
@@ -15,7 +15,7 @@
  * Copyright (c) 2013-2015 Los Alamos National Security, LLC.  All rights
  *                         reserved.
  * Copyright (c) 2016-2017 IBM Corporation. All rights reserved.
- * Copyright (c) 2018      Triad National Security, LLC. All rights
+ * Copyright (c) 2018-2025 Triad National Security, LLC. All rights
  *                         reserved.
  * $COPYRIGHT$
  *
@@ -134,12 +134,12 @@ OMPI_DECLSPEC extern ompi_predefined_win_t *ompi_mpi_win_null_addr;
 
 int ompi_win_init(void);
 
-int ompi_win_create(void *base, size_t size, int disp_unit,
+int ompi_win_create(void *base, size_t size, ptrdiff_t disp_unit,
                     ompi_communicator_t *comm, opal_info_t *info,
                     ompi_win_t **newwin);
-int ompi_win_allocate(size_t size, int disp_unit, opal_info_t *info,
+int ompi_win_allocate(size_t size, ptrdiff_t disp_unit, opal_info_t *info,
                       ompi_communicator_t *comm, void *baseptr, ompi_win_t **newwin);
-int ompi_win_allocate_shared(size_t size, int disp_unit, opal_info_t *info,
+int ompi_win_allocate_shared(size_t size, ptrdiff_t disp_unit, opal_info_t *info,
                       ompi_communicator_t *comm, void *baseptr, ompi_win_t **newwin);
 int ompi_win_create_dynamic(opal_info_t *info, ompi_communicator_t *comm, ompi_win_t **newwin);
 int ompi_win_free(ompi_win_t *win);