• by Wendy Davis  @wendyndavis, April 13, 2005

In a deal signaling the e-mail marketing industry's growing concern about spam filters, e-mail services company Return Path last week acquired Bonded Sender, a whitelist company that guarantees that e-mail won't end up in some of the larger "junk" mail folders.

Bonded Sender has deals with key Internet Service Providers--including MSN, Hotmail, and Roadrunner--and certain corporate accounts, under which the e-mail hosts agree to deliver messages from marketers on the Bonded Sender whitelist. Bonded Sender also has relationships with filtering applications, such as Spam Assassin.

A Bigfoot Interactive survey unveiled in March revealed that 32 percent of online consumers reported that mail they had requested from a trusted source was delivered to a spam folder.

Marketers who wish to be on Bonded Sender's roster must post a bond after being vetted by TRUSTe. The bond amount varies depending on the number of messages being sent; at the high end, it's around $4,000, said George Bilbrey, Return Path's vice president and general manager for the company's "delivery assurance solutions" division.

If complaints against a marketer on the list exceed a threshold percentage, Bonded Sender fines the company $20 per complaint, up to the amount of the bond. Bonded Sender also suspends marketers who have generated too many complaints from the program, said Bilbrey.

Marketers pay an application fee and an annual license fee, which varies from a couple of hundred dollars a year to a high of $10,000, Bilbrey said. The fee is based on the number of e-mails sent each year.

Return Path clients tend to send mail to between 100,000 and 20 million e-mail accounts, according to Bilbrey. Between 10 and 15 percent of Return Path's current clients also use Bonded Sender, said Bilbrey.

Bonded Sender was previously owned by IronPort. Scott Weiss, founder and CEO of IronPort, will now join Return Path's board of directors.