The (American) Direct Marketing Association ("The DMA") is a pro-spam group, not an anti-spam group. The DMA's mission is to advance the interests of junk email senders. The DMA is an out-of-touch but well-funded association that lobbies against spam laws in the United States. The position of the DMA is that "spam is freedom of commercial speech", and that the rights of their members to send you spam override your rights to not have your private email mailbox filled with unwanted spam at your expense. The DMA therefore advocate Opt-out (spamming) instead of Opt-in (permission-based marketing).
The DMA's opt-out E-mail Preference Service ([eMPS](http://www.dmaconsumers.org/consumers/optoutform_emps.shtml)) is a sham to pretend to U.S. Congress that spammers can self-regulate themselves. It will not get you off any spammers lists so don't waste your time.
Spamhaus knows of no U.S. firm using the DMA's eMPS service that isn't automatically [by definition](https://www.spamhaus.org/faqs/general-definitions/#what-is-the-definition-of-spam) a firm sending spam. The sole reason for users to need to opt-out of bulk email advertising they did not opt-in to is because the sender is sending without consent. Any DMA member that is using eMPS is using it because he is sending Unsolicited Bulk Email (UBE), i.e: Spam. The sending of UBE is against the terms of service of all Internet Service Providers, against the laws of Europe and Australia, and is grounds for listing the Sender on the Spamhaus Block List (SBL).