When it comes to email postage “tax” schemes, Jason Lee Miller of WebProNews discovered that Google is definitely against them.

Corporate communicator Eileen Rodriguez told him:

Gmail does not accept payment to bypass its filters, nor are there plans to charge senders to reach Gmail users.

Google’s refusal to accept payment plops the world’s largest search company squarely on the same bench with the world’s largest software company… for once.

But while both companies refuse to accept postage, Microsoft doesn’t mind if someone else collects it. In fact, Redmond endorsed IronPort’s Bonded Sender program, which did not share postage revenue with service providers.

Instead, senders paid Bonded Sender directly for “bonding” messages, to assure prompt delivery. The system used a DNS-like query system, with third-party watchdog, TRUSTe, vetting senders.

The program, however, was plagued by spam complaints. After four years of battle, IronPort sold it to direct marketing specialist, Return Path.

The ink on the contracts was barely dry before Return Path beefed up monitoring and certification requirements, then changed the name to Sender Score Certified.

Return Path officials claim that, since taking over, they have dumped 25% of the previously approved IP addresses.

“Because we now track upward of 60 data points from more than 45 million email boxes when gathering reputation data, we can see with great accuracy when senders are violating the standards,” said George Bilbrey, Return Path’s GM of Delivery Assurance Solutions. “Using that data, we can keep the program quality extremely high, ensuring that companies using Sender Score Certified are truly worthy of accreditation.”

Participating service providers, including MSN Hotmail, Windows Live Mail Beta and Roadrunner, do not share economically in the transaction. No mention of Google.

If you think it’s hard to keep a system clean even with completely disinterested third-party gatekeepers, imagine how tough it would be when both sides share the profits.

Remember when AOL and Yahoo endorsed GoodMail last January? The idea that GoodMail shares its postage revenue with email providers undermined the program from the start.

And it didn’t help that, while Yahoo stressed the value of assured delivery for financial institutions, AOL was spotted holding training sessions for mass mailers.

Neither seemed to clearly grasp the difference between being a disinterested gatekeeper, and being a gatekeeper on the take.

But the rest of the world was way ahead of them.

Organizations from DearAOL to the Electronic Frontier Foundation to the American Association of Retired Persons pummeled the three companies mercilessly, for both taxing email and selling out to spammers.

Since then, Yahoo has cooled to the idea considerably, while AOL appears to be ever less likely to pull the trigger.

Email Battles Backgrounder: