Large lists should follow FTC guidelines for bulk email stating how to unsubscribe, who it was sent from and why.
ftc.gov/tips-advice/business-center/guidance/can-spam-act-compliance-guide-business
For Example:
“This message was sent to students in the IT major by the IT Office to publish program updates. unsubscribe from this list IT Office · 1411 ITO Brigham Young University · Provo, UT 84602 · USA”
Make sure the subject line is:
Default bottom banner.
Follow the above steps to add a banner with an appropriate list description
Then copy the following text into your banner, changing LISTNAME to the name of your list:
########################################################################
To unsubscribe from the &LISTNAME list, click the following link:
.BB (&LITE = 0) and (&KWD(MAIL-MERGE,1) = YES)
&*TICKET_URL(&LISTNAME_ENCODED,SIGNOFF);
.ELSE
&WA_URL;?SUBED1=&LISTNAME_ENCODED&A=1
.EB
The unsubscribe ticket command can be put inside an HTML link as follows:
<a href="&*TICKET_URL(LISTNAME,SIGNOFF);">unsubscribe</a>.
The ticket only method of unsubscription requires your list to be configured with the Mail-merge setting on to create individualized links for each user:
The Mail-Merge setting can be abused by list senders and is NOT appropriate for public, unmoderated lists. It can only be set by a list administrator. Contact OIT communications support to make this change.
Communications Support has administrative access to enable Mail-Merge for 2 click unsubscription tied to individual users under:
List Management > List Configuration > List Configuration Wizard >>> Other [settings tab]
Verify with the List Owner that they trust list senders not to abuse the scripting capabilities of Mail-Merge.