AOL overview

AOL began its business operations in the 1980s and is considered to be one of the first Internet Service Providers (ISP). It originally provided dial up service to millions of Americans during the early days of the Internet. During the peak of the Internet dot-com boom in 2001, it merged with media conglomerate Time Warner Cable. Under new leadership In the late 2000s, AOL expanded its reach in to digital content by acquiring brands such as The Huffington Post, Tech Crunch, Engadget and Moviefone.

AOL was acquired by Verizon in May, 2015. Verizon also acquired Yahoo! in July, 2016. 

AOL is considered to be a global mailbox provider because it still owns a significant part of the email market at approximately 24 million subscribers.

Note: Starting February 1, 2018, Oath (A Verizon company that owns both AOL and Yahoo!) began consolidating sending infrastructures between AOL and Yahoo!. This means that the AOL domains will continue to operate and accept email, but Yahoo! will handle spam filtering and processing.

You can get additional information about the changes and the impact here:

• Oath to Combine Yahoo and AOL Email Infrastructures
• FAQ: Oath migration and Certification impact

We recommend that you follow best practices for both AOL and Yahoo! during this transition period.

Infrastructure

Return Path's partnership with AOL

In partnership with Return Path, AOL uses Return Path's Certified Whitelist. Senders participating in in Return Path's Certification program receive improved deliverability at AOL.

AOL delivery mediation 

Through Yahoo!, AOL has a public escalation process, which allows senders to open a trouble ticket.

AOL also has extensive information about the error codes they return available on their Postmaster website.