AOL contends that nothing would change for people currently using free Web mail, arguing that it would lose subscribers to its many competitors if it failed to maintain a quality service.
For companies or marketers, however, the paid system would guarantee their email and all its contents, including attachments, would reach customers, or potential customers. Spam filters today often send legitimate mail to junk folders by mistake, or strip away links and attachments to battle against phishers and virus writers.
Collectively, the coalition could reach between 2 million and 4 million AOL subscribers just through their own memberships, Pariser said.
Nevertheless, AOL said it wouldn't be swayed by the coalition.
"We have the facts on our side, we have our members on our side and we have the credibility and recognition of doing the right thing for years, when it comes to safety and security and protecting the integrity of email on the Internet," AOL spokesman Nicholas Graham said. "We have stellar, totally pristine deliverability practices for email that will not change, and the plan, as it always has been, remains today.
"AOL will implement certified email in the next 30 days. Mark it on your calendar."
While most of the coalition did not plan to call for a boycott of AOL, Larry Pratt, executive director of Gun Owners of America, said his organization would, if AOL went ahead with its service.
"If AOL pulls the trigger on this plan, then that would be our response," Pratt said.
The coalition has chosen to go after AOL and not Yahoo, because the latter in meetings appeared more tentative about launching the service.
"We really felt that AOL had planted its flag in the ground much more clearly," Danny O'Brien, activism coordinator for the Electronic Frontier Foundation, said.
In addition, AOL was a large enough target that if the portal decided to nix the service, it would discourage other portals from trying something similar, O'Brien said.