new file mode 100644
--- /dev/null
+++ b/proxy_ssl_certificate_empty.t
@@ -0,0 +1,108 @@
+#!/usr/bin/perl
+
+# (C) Sergey Kandaurov
+# (C) Nginx, Inc.
+
+# Tests for http proxy module with proxy certificate to ssl backend.
+# The proxy_ssl_certificate directive empty value cancels inheritance.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+my $t = Test::Nginx->new()->has(qw/http http_ssl proxy/)
+	->has_daemon('openssl');
+
+$t->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    server {
+        listen       127.0.0.1:8080;
+        server_name  localhost;
+
+        proxy_ssl_session_reuse off;
+
+        proxy_ssl_certificate 1.example.com.crt;
+        proxy_ssl_certificate_key 1.example.com.key;
+
+        location /verify {
+            proxy_pass https://127.0.0.1:8081/;
+        }
+
+        location /cancel {
+            proxy_pass https://127.0.0.1:8081/;
+            proxy_ssl_certificate "";
+            proxy_ssl_certificate_key "";
+        }
+    }
+
+    server {
+        listen       127.0.0.1:8081 ssl;
+        server_name  localhost;
+
+        ssl_certificate 2.example.com.crt;
+        ssl_certificate_key 2.example.com.key;
+
+        ssl_verify_client optional;
+        ssl_client_certificate 1.example.com.crt;
+
+        location / {
+            add_header X-Verify $ssl_client_verify;
+        }
+    }
+}
+
+EOF
+
+$t->write_file('openssl.conf', <<EOF);
+[ req ]
+default_bits = 2048
+encrypt_key = no
+distinguished_name = req_distinguished_name
+[ req_distinguished_name ]
+EOF
+
+my $d = $t->testdir();
+
+foreach my $name ('1.example.com', '2.example.com') {
+	system('openssl req -x509 -new '
+		. "-config $d/openssl.conf -subj /CN=$name/ "
+		. "-out $d/$name.crt -keyout $d/$name.key "
+		. ">>$d/openssl.out 2>&1") == 0
+		or die "Can't create certificate for $name: $!\n";
+}
+
+sleep 1 if $^O eq 'MSWin32';
+
+$t->write_file('index.html', '');
+
+$t->try_run('no empty value support')->plan(2);
+
+###############################################################################
+
+like(http_get('/verify'), qr/X-Verify: SUCCESS/ms, 'verify certificate');
+like(http_get('/cancel'), qr/X-Verify: NONE/ms, 'cancel certificate');
+
+###############################################################################