User-agent: Yandex
Disallow: /reg
Disallow: /reg.php
Disallow: /reg.php/

User-agent: Googlebot
Disallow: /reg
Disallow: /reg.php
Disallow: /reg.php/

User-agent: Mail.Ru
Disallow: /reg
Disallow: /reg.php
Disallow: /reg.php/

User-agent: *
Disallow: /reg
Disallow: /reg.php
Disallow: /reg.php/