[OCC]

depends

[InterceptPoint]

Here is how you do it:

Step 1 - Go to the home of the person who sent you the e-mail.

Step 2 - Open up their e-mail system and go to "Sent Mail"

Step 3 - Find the e-mail in question and look at the bcc: entries.

Piece of cake. ;)

[TheWasteLand]

Not usually, but if the email server is configured incorrectly (or badly programmed) it could happen.

If you're really interested, technically, the BCC header is not standardized under RFC 2822, so it's possible that a particular implementation may be flawed and could "leak" the information.

So under certain circumstances, it can happen.

[OCC]

If you had access to the mail server that sent the message, you may be able to see the BCC list. There is no way for the person receiving a BCC message to see who else it was sent to.