As a cross-sector, transnational organization devoted to eradicating cyber risk, at GCA we are dedicated to improving cybersecurity in a connected world. The DMARC authentication tool is an important step in supporting this mission. DMARC was developed as a collaborative effort to fight phishing and other dangerous email scams. Learn more about our involvement with DMARC.

DMARC Benefits

Brand Protection

  • Prevents spammers or phishers from using valid organization names.
  • Increases customer confidence and trust.
  • Improved deliverability of messages to Inbox.

Inbox Protection

  • Supported by 85% of consumer U.S. inboxes (Google, Yahoo, Microsoft).
    ~76% consumer inboxes worldwide are protected by DMARC. (4.8 billion mailboxes worldwide)


  • Reports provide information on authorized and unauthorized systems sending mail using the organization’s domain.


Starting in 2011 as an idea from a group of like-minded organizations, DMARC was formed as an effort to combat fraudulent email. Organization leaders wanted to enable email senders to create and archive policies on unauthenticated email while providing reporting on authentication infrastructure.

The tool started as a result of experience during “loose collaborations between some of the founding senders and receivers” who landed on an agreement in regards to how to interpret emails from domains supporting DKIM and SPF.

The authentication tool was officially published in 2012, and went public on the internet in 2013.

Learn more about the history of DMARC.

Founding Contributors

DMARC was created and first implemented by a group of committed organizations.


AOL, Comcast, GMail, Hotmail, Netease, Yahoo! Mail


American Greetings, Bank of America, Facebook, Fidelity, JPMorgan Chase & Co., LinkedIn, PayPal

Intermediaries & Vendors

Agari, Cloudmark, Return Path, Trusted Domain Project

GCA Partners Using DMARC

About the Global Cyber Alliance

Contact GCA

The Global Cyber Alliance is based in New York City and London with collaborating partners located around the world. To contact us, please reach out to our main headquarters by email, or phone, or send us a message using the form here.

  • +1.646.677.5535

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