Filter Gmail Messages on Bcc field
Gmail filters have a number of fields and functions that aren’t well documented. One of the things that I wanted to do was filter all messages based on the bcc field. In order to do this, you need to learn about the deliveredto operator. If the bcc’d messages go to a unique address, your filter would look like this:
deliveredto:myemail+specialcode@gmail.com
To truly filter messages that are only received via bcc but that don’t have a special email address that they go to, you’ll need to do it this way:
deliveredto:myemail@gmail.com AND -to:myemail@gmail.com AND -cc:myemail@gmail.com
Enjoy!