diff --git a/top/top.c b/top/top.c
index ea1a8fe2..a40b1d33 100644
--- a/top/top.c
+++ b/top/top.c
@@ -82,6 +82,7 @@ static sigset_t Sigwinch_set;
 static char  Rc_name [OURPATHSZ];
 static RCF_t Rc = DEF_RCFILE;
 static int   Rc_questions;
+static int   Rc_compatibilty;
 
         /* SMP, Irix/Solaris mode, Linux 2.5.xx support (and beyond) */
 static long        Hertz;
@@ -3613,6 +3614,10 @@ static const char *configs_file (FILE *fp, const char *name, float *delay) {
    if (Rc.zero_suppress < 0 || Rc.zero_suppress > 1)
       Rc.zero_suppress = 0;
 
+   // prepare to warn that older top can no longer read rcfile ...
+   if (Rc.id != RCF_VERSION_ID)
+      Rc_compatibilty = 1;
+
    // lastly, let's process any optional glob(s) ...
    // (darn, must do osel 1st even though alphabetically 2nd)
    fbuf[0] = '\0';
@@ -4638,6 +4643,12 @@ static void write_rcfile (void) {
          return;
       Rc_questions = 0;
    }
+   if (Rc_compatibilty) {
+      show_pmt(N_txt(XTRA_warnold_txt));
+      if ('y' != tolower(iokey(1)))
+         return;
+      Rc_compatibilty = 0;
+   }
    if (!(fp = fopen(Rc_name, "w"))) {
       show_msg(fmtmk(N_fmt(FAIL_rc_open_fmt), Rc_name, strerror(errno)));
       return;
diff --git a/top/top_nls.c b/top/top_nls.c
index c69385df..cfb90321 100644
--- a/top/top_nls.c
+++ b/top/top_nls.c
@@ -509,6 +509,7 @@ static void build_norm_nlstab (void) {
    Norm_nlstab[XTRA_vforest_fmt] = _("PID to collapse/expand [default pid = %d]");
    Norm_nlstab[XTRA_size2up_txt] = _("terminal is not wide enough");
    Norm_nlstab[XTRA_modebad_txt] = _("wrong mode, command inactive");
+   Norm_nlstab[XTRA_warnold_txt] = _("saving prevents older top from reading, save anyway?");
 }
 
 
diff --git a/top/top_nls.h b/top/top_nls.h
index e728b763..daee67bd 100644
--- a/top/top_nls.h
+++ b/top/top_nls.h
@@ -83,7 +83,7 @@ enum norm_nls {
    WORD_eachcpu_fmt, WORD_exclude_txt, WORD_include_txt, WORD_noneone_txt,
    WORD_process_txt, WORD_threads_txt, WRITE_rcfile_fmt, WRONG_switch_fmt,
    XTRA_badflds_fmt, XTRA_fixwide_fmt, XTRA_modebad_txt, XTRA_size2up_txt,
-   XTRA_vforest_fmt, XTRA_warncfg_txt, XTRA_winsize_txt,
+   XTRA_vforest_fmt, XTRA_warncfg_txt, XTRA_warnold_txt, XTRA_winsize_txt,
 #ifndef INSP_OFFDEMO
    YINSP_demo01_txt, YINSP_demo02_txt, YINSP_demo03_txt, YINSP_deqfmt_txt,
    YINSP_deqtyp_txt, YINSP_dstory_txt,