Google: "You were BCC'd on this message" Banner in Gmail Reply

This article provides information on the following alert that may appear when replying to a message in Gmail: "You were BCC'd on this message. Replying to all lets everyone know you were included."

Environment

U-M Google, Gmail

Issue

• When replying all to an email in Gmail, I receive the following banner: "You were BCC'd on this message. Replying to all lets everyone know you were included." What does this mean?
• I received an email because I'm a member of an MCommunity group or Shared Account group. That group/account was not BCC'd. Why does this banner appear when I reply all to the message?

Resolution

• Google displays this banner in the compose box when you reply all to an email where you were BCC'd.
• However, this banner may also appear when replying all to an MCommunity group or Shared Account.
  • This affects both public and private MCommunity groups and Shared Accounts with group members (who receive messages sent to the address).
• Because of how MCommunity groups function within U-M Google, Google interprets these groups as having members who are "hidden" from recipients and other group members.
  • Because your account's email address is not explicitly named within the reply field, if you reply all, it will display the banner claiming you are replying all to a BCC, even when you're not.
  • An example where this would be important to notify you about is if the group you're replying all to has external members. While you have access to MCommunity to view the group members (as someone with an @umich.edu email address and membership to the group), other non-UM external members do not. You would be revealing to these external members that you are also a member of this group by replying all.

Additional Information

• Google Workspace Update regarding the banner
• Screenshot of the banner is attached to this article

Need additional information or assistance? Contact the ITS Service Center.