1. Go to lists.oregonstate.edu
2. Log into the list you would like to manage
3. Click on privacy options
4 Scroll down to the section "List of addresses which are banned from membership in this mailing list."
5. In the text box copy and paste the line of text below, this line only allows OSU/OUS addresses to subscribe to this list. This is typically used to prevent list subscription spam.
If you'd like non OSU emails to subscribe to this list, remove that line from the Ban List.
6. Click on Submit Your Changes
If you're concerned about unwanted subscription spam, you can use the Subscribe Policy setting on the same page (http://lists.oregonstate.edu/mailman/admin/iamslic-exec/privacy). A brief explanation of the options for Subscribe Policy follows:
confirm - subscriber confirms via clicking on URL sent to them in email
require approval - list admin approves the request; no email confirmation sent to subscriber
confirm and approve - subscriber confirms via email AND list admins approves the request
Confirm and approve is best bet again subscription spam if you remove the address restriction in the Ban List.