For $1,375/year you can send SPAM to Microsoft, AOL and Comcast customers

Quote from the website: "Return Path’s Certification program is the industry’s most recognized and valued certified whitelist. Getting on the whitelist helps ensure better inbox placement with major mailbox providers like Yahoo, Microsoft, AOL, Comcast, and more.

21 percent of promotional emails never reach the inbox, landing in spam folders or getting blocked. That means losing out on opens, clicks, and ultimately revenue–impacting the success or failure of your email programs. Don’t take that risk. Partner with Return Path to optimize email visibility and increase revenue by getting more email delivered."

Here is the price list: https://returnpath.com/wp-content/uploads/2015/06/Return-Pat...

About $10 per thousand messages.

There are an awful lot of deliverability​ service providers out there. This is nothing new. Amazon SES is priced about the same and has the same requirements to keep your lists clean.