diff --git a/rptflt/rptflt.pl b/rptflt/rptflt.pl
new file mode 100755
index 0000000..e141f8a
--- /dev/null
+++ b/rptflt/rptflt.pl
@@ -0,0 +1,104 @@
+#!/usr/bin/perl
+#
+# rptflt.pl - Filter known issues from KiCad DRC reports
+#
+# Written 2014 by Werner Almesberger
+# Copyright 2014 Werner Almesberger
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+
+#
+# Usage:
+#
+# - generate a DRC report file with pcbnew, e.g., foo.rpt
+# - review report file for any real issues
+# - rename foo.rpt to foo.exceptions
+# - to check for new errors, generate new report file, then run
+#   rptflt.pl foo.exceptions foo.rpt
+#
+
+
+sub compact
+{
+	local ($m);
+
+	die if $#e != 2;
+	die unless $e[0] =~ /^ErrType\(\d+\):\s+(.*)\s*$/;
+	$m = $1;
+	die unless $e[1] =~ /^\s+@[^:]++:\s+(.*)\s*$/;
+	$m .= "; $1";
+	die unless $e[2] =~ /^\s+@[^:]+:\s+(.*)\s*$/;
+	$m .= "; $1";
+	return $m;
+}
+
+
+sub add
+{
+	local ($m);
+
+	$m = &compact;
+	$exc{$m} = 1;
+	undef @e;
+}
+
+
+sub filter
+{
+	local ($m);
+
+	$m = &compact;
+	if (defined $exc{$m}) {
+		$seen{$m} = 1;
+	} else {
+		print join("", @e);
+	}
+	undef @e;
+}
+
+
+sub process
+{
+	open(FILE, $_[0]) || die "$_[0]: $!";
+	undef @e;
+	while (<FILE>) {
+		if (/^ErrType/) {
+			&flush if @e;
+			@e = ($_);
+			next;
+		}
+		if (/^\s+@/) {
+			die unless @e;
+			push(@e, $_);
+			next;
+		}
+		&flush if @e;
+		print unless $silent;
+	}
+	&flush if @e;
+	close FILE;
+}
+
+
+if ($#ARGV != 1) {
+	print stderr "usage: $0 name.exceptions name.rpt\n";
+	exit(1);
+}
+
+
+*flush = *add;
+$silent = 1;
+&process($ARGV[0]);
+*flush = *filter;
+$silent = 0;
+&process($ARGV[1]);
+
+for $m (keys %exc) {
+#print STDERR "check $i\n";
+	next if $seen{$m};
+	print STDERR "Warning: exception \"$m\" not seen\n";
+}