Users can send a referral email or voicemail through the ad unit to a chosen recipient for viral campaigns. All such ads must meet the following criteria:
- Email addresses and phone numbers may not be used for any other purpose except to share the ad.
- The ad must include both a 'To' and a 'From' field for the user to populate.
- The tell-a-friend feature may not be used in an ad that provides an incentive for sharing the ad with a friend (e.g. coupon, movie tickets, cash).
- The ad backend must include a cap on the number of referrals that can be sent to one particular email address or phone number from a particular ad. This cap is per campaign.
Additionally, for tell-a-friend email:
- Email messages must contain a link to, or information about, the ad and/or product/service promoted.
- Email messages must clearly identify both the advertiser and the user who sent the ad (e.g. a "To" and "From" field; should say 'John Doe, Jane Doe has sent you a message").
- Email messages must include advertiser's postal address.
- All messages that are sent through advertiser's backend must include an easy-to-understand opt-out method for the receiver of the email that complies with CAN-SPAM regulations.
- The limit to the number of allowable messages sent is three referral emails per ad to any one email address.
Additionally, for offline message service:
- Users can send a voice mail to a chosen recipient using an IVR provider.
- Voice mail must clearly identify both the advertiser and the user who sent the ad.
- The limit to the number of allowable messages sent is one referral voicemail per ad to any one phone number.