diff --git a/src/nvim/sign.c b/src/nvim/sign.c
index a5adc48540..0e4d092025 100644
--- a/src/nvim/sign.c
+++ b/src/nvim/sign.c
@@ -1176,21 +1176,27 @@ static void sign_define_cmd(char_u *sign_name, char_u *cmdline)
     p = skiptowhite_esc(arg);
     if (STRNCMP(arg, "icon=", 5) == 0) {
       arg += 5;
+      XFREE_CLEAR(icon);
       icon = vim_strnsave(arg, (size_t)(p - arg));
     } else if (STRNCMP(arg, "text=", 5) == 0) {
       arg += 5;
+      XFREE_CLEAR(text);
       text = vim_strnsave(arg, (size_t)(p - arg));
     } else if (STRNCMP(arg, "linehl=", 7) == 0) {
       arg += 7;
+      XFREE_CLEAR(linehl);
       linehl = vim_strnsave(arg, (size_t)(p - arg));
     } else if (STRNCMP(arg, "texthl=", 7) == 0) {
       arg += 7;
+      XFREE_CLEAR(texthl);
       texthl = vim_strnsave(arg, (size_t)(p - arg));
     } else if (STRNCMP(arg, "culhl=", 6) == 0) {
       arg += 6;
+      XFREE_CLEAR(culhl);
       culhl = vim_strnsave(arg, (size_t)(p - arg));
     } else if (STRNCMP(arg, "numhl=", 6) == 0) {
       arg += 6;
+      XFREE_CLEAR(numhl);
       numhl = vim_strnsave(arg, (size_t)(p - arg));
     } else {
       semsg(_(e_invarg2), arg);
diff --git a/test/functional/ex_cmds/sign_spec.lua b/test/functional/ex_cmds/sign_spec.lua
index 891cfe1670..f280a45174 100644
--- a/test/functional/ex_cmds/sign_spec.lua
+++ b/test/functional/ex_cmds/sign_spec.lua
@@ -1,5 +1,5 @@
 local helpers = require('test.functional.helpers')(after_each)
-local clear, nvim, eq = helpers.clear, helpers.nvim, helpers.eq
+local clear, nvim, eq, assert_alive = helpers.clear, helpers.nvim, helpers.eq, helpers.assert_alive
 
 describe('sign', function()
   before_each(clear)
@@ -21,4 +21,11 @@ describe('sign', function()
       end)
     end)
   end)
+
+  describe('define {id}', function()
+    it ('does not leak memory when specifying multiple times the same argument', function()
+      nvim('command', 'sign define Foo culhl=Normal culhl=Normal')
+      assert_alive()
+    end)
+  end)
 end)