diff --git a/util/maint/create_patches.sh b/util/maint/create_patches.sh
index 7c1655f..339136a 100755
--- a/util/maint/create_patches.sh
+++ b/util/maint/create_patches.sh
@@ -44,11 +44,9 @@
 SCRIPT_NAME=`basename "$0"`
 SCRIPT_DIR=$(cd "$REL_SCRIPT_DIR" && echo "$(pwd -P)")
 MSG_FILTER="$SCRIPT_DIR"/upstream_msg_filter.sed
-CONV_HG="$SCRIPT_DIR"/git-patch-to-hg-patch
 
 PATCH_DIR="./patches/"
 UPSTREAM="upstream/master"
-PATCH_FORMAT=
 
 usage()
 {
@@ -59,7 +57,6 @@
 Options:
   -u BRANCH      Upstream branch
   -d DIR         Patch directory
-  -f FMT         Patch format (hg or git)
   -h             Show this help string.
 
 This script creates a series of patches suitable from upstream
@@ -70,7 +67,7 @@
   1. Rebase the patches in the current branch onto the upstream
      branch.
   2. Filter commit messages.
-  3. Generate a set of patches in git format or Mercurial format.
+  3. Generate a set of patches in git format.
 EOF
 }
 
@@ -79,7 +76,7 @@
     git rev-parse --verify -q "$1" > /dev/null
 }
 
-while getopts ":u:d:f:h" OPT; do
+while getopts ":u:d:h" OPT; do
     case $OPT in
         d)
             PATCH_DIR="$OPTARG"
@@ -87,9 +84,6 @@
         u)
             UPSTREAM="$OPTARG"
             ;;
-        f)
-            PATCH_FORMAT="$OPTARG"
-            ;;
         h)
             usage
             exit 0
@@ -117,21 +111,6 @@
 
 BRANCH="${1:-HEAD}"
 
-case "$PATCH_FORMAT" in
-    git|hg)
-        ;;
-
-    "")
-        echo "Error: No patch format specified" >&2
-        exit 1
-        ;;
-
-    *)
-        echo "Error: Illegal patch format specified: '$PATCH_FORMAT'" >&2
-        exit 1
-esac
-
-
 if ! branch_exists "$BRANCH"; then
     echo "Error: Patch branch '$BRANCH' doesn't exist" 1>&2
     exit 2
@@ -168,10 +147,3 @@
 
 echo "Creating patches..."
 git format-patch -p -o "$PATCH_DIR" "$UPSTREAM"
-
-if [ "$PATCH_FORMAT" == "hg" ]; then
-    echo "Converting patches..."
-    for P in "$PATCH_DIR"/*.patch; do
-        "$CONV_HG" $P
-    done
-fi
diff --git a/util/maint/git-patch-to-hg-patch b/util/maint/git-patch-to-hg-patch
deleted file mode 100755
index 1b9e05d..0000000
--- a/util/maint/git-patch-to-hg-patch
+++ /dev/null
@@ -1,137 +0,0 @@
-#!/usr/bin/env python2
-#
-# This file originated from the moz-git-tools repo on GitHub
-# (https://github.com/mozilla/moz-git-tools), which contains the
-# following LICENSE notice:
-#
-# <quote>
-# Except for git-new-workdir, which is covered under GPLv2, the code
-# in this repository is placed into the public domain via CC0.
-#
-# http://creativecommons.org/publicdomain/zero/1.0/legalcode
-# </quote>
-
-r"""Git format-patch to hg importable patch.
-
-(Who knew this was so complicated?)
-
->>> process(StringIO('From 3ce1ccc06 Mon Sep 17 00:00:00 2001\nFrom: fromuser\nSubject: subject\n\nRest of patch.\nMore patch.\n'))
-'# HG changeset patch\n# User fromuser\n\nsubject\n\nRest of patch.\nMore patch.\n'
-
->>> process(StringIO('From: fromuser\nSubject: A very long subject line.  Lorem ipsum dolor sit amet, consectetur adipiscing elit. Morbi faucibus, arcu sit amet\n\nRest of patch.\nMore patch.\n'))
-'# HG changeset patch\n# User fromuser\n\nA very long subject line.  Lorem ipsum dolor sit amet, consectetur adipiscing elit. Morbi faucibus, arcu sit amet\n\nRest of patch.\nMore patch.\n'
-
->>> process(StringIO('From: f\nSubject: =?UTF-8?q?Bug=20655877=20-=20Dont=20treat=20SVG=20text=20frames=20?= =?UTF-8?q?as=20being=20positioned.=20r=3D=3F?=\n\nPatch.'))
-'# HG changeset patch\n# User f\n\nBug 655877 - Dont treat SVG text frames as being positioned. r=?\n\nPatch.'
-"""
-
-# Original author: bholley
-
-import sys
-import re
-import fileinput
-import email, email.parser, email.header, email.utils
-import math
-from cStringIO import StringIO
-from itertools import takewhile
-
-def decode_header(hdr_string):
-  r"""Clean up weird encoding crap.
-
-  >>> clean_header('[PATCH] =?UTF-8?q?Bug=20655877=20r=3D=3F?=')
-  '[PATCH] Bug 655877 r=?'
-  """
-  rv = []
-  hdr = email.header.Header(hdr_string, maxlinelen=float('inf'))
-  for (part, encoding) in email.header.decode_header(hdr):
-    if encoding is None:
-      rv.append(part)
-    else:
-      rv.append(part.decode(encoding).encode('utf-8'))
-  return ' '.join(rv)
-
-def clean_header(hdr_string):
-  r"""Transform a header split over many lines into a header split only where
-  linebreaks are intended.  This is important because hg cares about the first
-  line of the commit message.
-
-  Also clean up weird encoding crap.
-
-  >>> clean_header('Foo\n bar\n baz')
-  'Foo bar baz'
-  >>> clean_header('Foo\n bar\nSpam\nEggs')
-  'Foo bar\nSpam\nEggs'
-  """
-
-  lines = []
-  curline = ''
-  for line in decode_header(hdr_string).split('\n'):
-    if not line.startswith(' '):
-      lines.append(curline)
-      curline = ''
-    curline += line
-  lines.append(curline)
-  return '\n'.join(lines[1:])
-
-def process(git_patch_file):
-  parser = email.parser.Parser()
-  msg = parser.parse(git_patch_file)
-  from_hdr = clean_header(msg['From'])
-  commit_title = clean_header(msg['subject'])
-  if not len(commit_title) or not len(from_hdr):
-    sys.stderr.write("%s does not look like a valid git patch file, skipping\n"
-                     % git_patch_file.name)
-    return
-
-  parsed_from = email.utils.parseaddr(from_hdr)
-  nuke_prefix = r"\[PATCH( \d+/\d+)?\] "
-  match = re.match(nuke_prefix, commit_title)
-  if match:
-    commit_title = commit_title[match.end():]
-
-  patch_body = msg.get_payload()
-
-  # git format-patch wraps the diff (including trailing whitespace):
-  #   ---
-  #   <diff>
-  #   --
-  #   2.0.3
-  # This doesn't hurt parsing the diff at all, but the version number is
-  # nonsense once the git specific items have been stripped
-  patch_body = re.sub(r'--\s?\n[0-9\.]+\n$', '', patch_body)
-
-  return '\n'.join(['# HG changeset patch',
-                    '# User %s <%s>' % parsed_from,
-                    '',
-                    commit_title,
-                    '',
-                    patch_body])
-
-if __name__ == "__main__":
-  if len(sys.argv) > 1 and sys.argv[1] == '--test':
-    import doctest
-    doctest.testmod()
-    sys.exit(0)
-
-  # If there were no arguments, do stdin->stdout.
-  filelist = sys.argv[1:]
-  if not filelist:
-    lines = process(sys.stdin)
-    sys.stdout.writelines(lines)
-    sys.exit(0)
-
-  # Otherwise, we take a list of files.
-  for filename in filelist:
-
-    # Read the lines.
-    f = open(filename, 'r')
-    lines = process(f)
-    f.close()
-
-    # Process.
-
-    if lines:
-      # Write them back to the same file.
-      f = open(filename, 'w')
-      f.writelines(lines)
-      f.close()