FAQs For Senders / ESPs

What is BIMI?

Brand Indicators for Message Identification or BIMI (pronounced: Bih-mee) is an emerging email specification that enables the use of brand-controlled logos within supporting email clients. BIMI leverages the work an organization has put into deploying DMARC protection, by bringing brand logos to the customer’s inbox. For the brand’s logo to be displayed, the email must pass DMARC authentication checks, ensuring that the organization’s domain has not been impersonated.

How does BIMI technically work?

BIMI allows an organization to publish a new, standardized DNS record for a domain they own. This record contains a URL to a logo that may require proof that the logo has been validated with a VMC. An organization will publish a BIMI record containing these URLs. A supporting mailbox provider (MBP) will check the sending domain’s DMARC policy and verify that it is included in the BIMI validation. If both checks are successful, the MBP may use the logo from the URL in the BIMI record to populate the BIMI image of the qualifying email sent from that domain to the MBP.

What is DMARC?

DMARC, which stands for “Domain-based Message Authentication, Reporting & Conformance,” is an email authentication policy and reporting protocol. DMARC defends against unauthorized use of domains by preventing direct domain impersonation within email. It protects brands by ensuring participating mailboxes only receive email actually sent by or on behalf of a domain. More information about DMARC.

What is DMARC Enforcement?

DMARC enforcement represents a particular attribute of a DMARC record “p=”.  This attribute indicates how the record holder authorizes the mail receiver to handle mail that fails DMARC and authentication checks. Enforcement can be “p=quarantine” which indicates failed messages should be quarantined, or “p=reject” which indicates failed messages should be rejected.

What does BIMI have to do with anti-abuse?

BIMI enhances your brand’s value within participating mailboxes, connecting the display of verified logos to the increased protection provided by DMARC enforcement. Building on the improved defense against domain impersonation and related decrease in abuse, BIMI supports increased trust with your brand.

Does BIMI use any technical means to validate the published logo?

To correctly assert logo association to a given message, the current BIMI specification relies on a successful validation of the BIMI record, relative to a sending domain. It is up to the domain and mark owner to reference the correct logo to use in a BIMI record for a domain.

What will my experience as a “Brand” and my customers be?

Compared to senders who do not implement BIMI, your brand logo may appear with your messages. Recipients may better recognize and interact with your messaging by making a visual connection to your brand logo and increase your brand’s engagement through direct customer response. BIMI may potentially improve email opens or clicks, as compared to messages sent without logo impressions in the user’s mailbox.

Does BIMI allow me to support multiple domains and logos?

Currently, BIMI supports one logo for multiple domains and subdomains. BIMI certificates (VMCs) – which some mail systems may require – each only support a single logo, which must be a trademark.

What do I need to do to operationalize BIMI on my end?

Senders will need an email sending domain with a DMARC policy of at least quarantine or reject. Some mailbox providers may require senders to obtain a verified mark certificate (VMC). Senders will need a logo, for which they own the mark, hosted on a URL that follows the specification parameters requirements. The final step is to build a simple BIMI DNS record and publish it to DNS.

Does the display of a logo promote user trust?

BIMI’s strong authentication requirement – DMARC at enforcement – provides brands the opportunity to prevent their domain(s) from abuse, therefore potentially improving trust with their customers. BIMI builds on this foundation of trust and authentication.

We have published our BIMI record; how do we verify it’s working?

Currently, BIMI is only live in production at Yahoo! and is available for viewing in both the webmail and the Yahoo! Mobile application (Google Play, iOS).

Verizon Media (Yahoo) will display your BIMI logo if :

  • A BIMI record exists which points to a valid logo in SVG format
  • A DMARC policy of quarantine or reject is in place
  • The mailing is sent to large number of recipients (bulk mail)
  • And Verizon Media sees sufficient reputation and engagement for the email address

If you think all of those requirements are met but still no logo is displayed, please reach out to Yahoo’s mail team for help.

My ESP doesn’t provide the ability for us to modify the SMTP.from (ex: bounce.esp.com, RFC 5321) domain when they send email on behalf of our domain. Will this be a problem for BIMI?

BIMI relies upon DMARC alignment passing (via SPF or DKIM). As long as DKIM alignment passes, your BIMI record will be retrieved and evaluated. Please check with your email service provider for options.

Should I only publish BIMI on my organizational domain or each subdomain?

According to the BIMI standards your records need to be published at the organization level, and differentiated by the records selector value for subdomain. However, some mailbox providers may choose to implement BIMI in their own way which is different from the standard recommendation.

Does BIMI use my DKIM (d=; i=) or my SPF domain?

Receivers will attempt to retrieve a BIMI record from the domain identified by DMARC alignment for the RFC5322.From Author Domain. In the case of DKIM alignment, the BIMI record would be retrieved from the domain identified within the DKIM “d=” value.

Does my policy need to be at quarantine/reject pct=100 to be considered enforcement?

If the DMARC policy for the organizational domain is p=quarantine, and the record defines a percentage tag, then that tag must be pct=100, otherwise the policy does not meet BIMI requirements.

Why is “Brand” logo showing while they don’t have a BIMI record?

In essence BIMI is an attempt at standardizing how logos are displayed and verified within email clients. The numerous processes that were mostly manual or relied on profiles in other applications and platforms are being harmonized and verified through aligned email authentication and DMARC enforcement. Certain Mailbox providers, such as Microsoft, have different mechanisms which will show logos, but this is not BIMI.

BIMI – is there a certain recommended logo size?

BIMI relies on a scale vector format, specifically described as an SVG profile (currently defined as SVG Tiny 1.2). As such, BIMI logos are not defined by pixel size, please consult your graphic designer for help in creating a proper vector graphic. Please review the specific requirements for logos in our other FAQs.