Does Cloudmark's BIMI support mean my logo will show up in all mailboxes that use Cloudmark?

Cloudmark primarily validates the BIMI record and stamps the relevant headers onto an email. However, the actual display of the logo is handled by the recipient's email client (Mail User Agent), which must independently support BIMI rendering.

What are the core technical requirements for implementing BIMI?

For BIMI to work, your domain must have a DMARC policy set to at least `p=quarantine` or `p=reject` . You also need an SVG Tiny 1.2 format logo and a BIMI DNS record. Some providers, like Gmail, also require a Verified Mark Certificate (VMC).

Which specific mailbox providers are known to support BIMI?

While Cloudmark does backend validation, the decision to display BIMI logos rests with the individual Mailbox Provider and their Mail User Agent. Major providers like Gmail, Yahoo Mail, Apple Mail, Fastmail, and La Poste generally support BIMI.

Will my BIMI logo appear if my email lands in the spam folder?

No, if an email is filtered into the spam or junk folder, the BIMI logo will typically not be displayed, even if it passes all BIMI authentication checks. BIMI is intended to enhance legitimate inbox delivery.

Which mailbox providers support BIMI through Cloudmark, and how is it implemented? - Technical - Email deliverability - Knowledge base

Understanding Brand Indicators for Message Identification (BIMI) is crucial for enhancing email trust and brand recognition. Many email marketers and deliverability professionals know the major players like Google and Yahoo Mail support BIMI, but questions often arise about other providers, especially those leveraging third-party security solutions like Cloudmark.

Cloudmark, a well-known email security vendor, offers services to various mailbox providers globally. This naturally leads to inquiries about how their services intersect with BIMI, specifically if Cloudmark's support for BIMI translates into widespread logo display across all its client mailbox providers. It is not as straightforward as it might seem.

Navigating the landscape of BIMI support requires understanding the different components involved in email processing, particularly the roles of Mail Transfer Agents (MTAs) and Mail User Agents (MUAs). My goal is to demystify how BIMI works with Cloudmark and which providers benefit, along with the essential implementation steps.

How Cloudmark facilitates BIMI

Cloudmark functions primarily as an email security platform, often serving as an MTA (Mail Transfer Agent) or a security layer before the email reaches the recipient's inbox. Cloudmark's role in BIMI support is to validate the BIMI record and stamp the necessary headers onto the email if the domain passes authentication, including DMARC. This validation is a crucial step in the BIMI process, ensuring that the brand's logo is legitimate and properly authenticated.

However, Cloudmark validating BIMI does not automatically mean every mailbox provider using Cloudmark will display the logo. The actual display of the BIMI logo is handled by the Mail User Agent (MUA), which is the email client itself, such as Apple Mail or Gmail's web interface. While Cloudmark provides the foundational validation, the MUA must be designed and configured to read and display these BIMI headers.

This distinction is vital. A mailbox provider might use Cloudmark for spam filtering and authentication, but if their specific email client (webmail or desktop application) does not support BIMI rendering, the logo will not appear. Therefore, BIMI support is a two-pronged approach, requiring both backend validation (which Cloudmark facilitates) and frontend rendering by the email client.

MTA vs. MUA

It's essential to differentiate between the Mail Transfer Agent (MTA) and the Mail User Agent (MUA) when discussing BIMI. The MTA is responsible for relaying email from one server to another, often performing initial security checks. The MUA is the email client that users interact with to send and receive messages.

MTA role: Cloudmark, acting as an MTA, validates the DMARC policy and the BIMI DNS record. If validated, it stamps the email with a BIMI header.
MUA role: The MUA (email client) then reads this BIMI header and, if it supports the standard, displays the brand's logo next to the sender's name in the inbox. Not all MUAs support BIMI display, even if the backend validates it.

Mailbox providers supporting BIMI via Cloudmark

While Cloudmark itself supports BIMI validation, identifying every specific mailbox provider that uses Cloudmark and also supports BIMI logo display can be complex. Many smaller or international providers license Cloudmark's technology. However, the BIMI Group provides an official list of known BIMI-supporting email clients and mailbox providers. Providers frequently update their support, so this list is the most reliable source for up-to-date information.

Historically, major players like Google (Gmail), Yahoo Mail, and Apple Mail have been at the forefront of BIMI adoption. These providers often have the resources to implement both the backend validation and the frontend display. While Cloudmark provides a service used by many, it's the individual mailbox provider's decision to fully integrate and activate the visual display of BIMI logos in their specific client interfaces.

For example, even if a provider like Cox uses Cloudmark for filtering, it does not guarantee that their webmail or native email client will display a BIMI logo. The distinction between an email service provider (ESP) and an email client (MUA) is critical here. An ESP like

iCloud might ensure emails sent to their addresses have the necessary BIMI headers, and a client like

Apple Mail (the app) simply reads those headers, regardless of which backend security provider processed the email.

Mailbox Provider	BIMI Support	Cloudmark Usage (for filtering)
Gmail (Google Workspace)	Yes, with VMC requirement	No, typically uses internal filtering
Yahoo Mail (incl. AOL, Netscape)	Yes, often without VMC requirement	Yes, widely uses Cloudmark
Apple Mail (iOS/macOS clients)	Yes, display based on headers	Uses Cloudmark and Proofpoint
Fastmail	Yes	No direct Cloudmark usage indicated
La Poste	Yes	Yes, uses Cloudmark
Onet Poczta	Yes	Yes, uses Cloudmark

Practical BIMI implementation and display

Implementing BIMI effectively requires a solid foundation in email authentication. The primary prerequisite is a DMARC policy set to at least `p=quarantine` or `p=reject`. Without this, mailbox providers (including those using Cloudmark) will not consider displaying your logo, as DMARC provides the necessary assurance that emails are legitimate.

Beyond DMARC, you'll need a Brand Indicator (your logo) in SVG Tiny 1.2 format and a BIMI DNS record. For some providers, like Gmail, a Verified Mark Certificate (VMC) is also required. A VMC provides an additional layer of trust, verifying that your organization legitimately owns the logo. This is where the intricacies of implementation come into play, as not all providers have the same requirements.

A common question is whether a BIMI logo will display if an email passes authentication but still lands in the spam folder. Generally, if an email is marked as spam, the logo will not be displayed, regardless of BIMI compliance. BIMI is designed to enhance legitimate mail, not to bypass spam filters. Therefore, maintaining a good sending reputation and ensuring high deliverability remains paramount, even with BIMI implemented.

Challenges in BIMI display

Client-side limitations: Not all email clients or webmail interfaces support BIMI logo rendering, even if the backend system (like Cloudmark) has validated the email.
VMC requirements: Some major mailbox providers, like Gmail, require a VMC to display the logo, adding complexity and cost.
Spam folder placement: If an email is classified as spam, even with valid BIMI, the logo is unlikely to appear in the recipient's spam folder, diminishing its impact.

Solutions and best practices

Prioritize DMARC enforcement: Ensure your DMARC policy is at `p=quarantine` or `p=reject`. This is the fundamental requirement for BIMI.
Obtain a VMC (if needed): For providers requiring it, secure a Verified Mark Certificate from an accredited authority.
Monitor deliverability: Continuously monitor email deliverability rates to ensure emails land in the inbox, where BIMI logos are most impactful.

Views from the trenches

Expert from Email Geeks says: Cloudmark primarily stamps headers that Mail User Agents (MUAs) like Apple Mail can then read and display the logo. It is crucial to decouple Apple Mail as a client from iCloud as an email service provider.

Expert from Email Geeks says: Cloudmark Gateway (CMGW) supports validating BIMI, but it is up to the individual mailbox provider to have a version with this feature enabled. CMGW is only the Mail Transfer Agent, so a Mail User Agent is also needed to interpret the BIMI headers.

Marketer from Email Geeks says: Mail that fails DMARC will not receive a BIMI logo. If an email passes DMARC but still ends up in the spam folder, whether the logo is displayed is less clear-cut, though typically it is not shown.

Marketer from Email Geeks says: From a user experience perspective, it would be beneficial if BIMI logos appeared in the spam folder for legitimate senders. This could help recipients identify false positives from senders who have invested in BIMI certification.

Best practices

Ensure your DMARC policy is set to quarantine or reject for optimal BIMI display.

Verify your SVG logo format rigorously to meet BIMI specifications, preventing display issues.

Continuously monitor BIMI display across various email clients and providers.

Obtain a Verified Mark Certificate (VMC) for major providers like Gmail that require it.

Common pitfalls

Assuming Cloudmark's backend support guarantees BIMI display in all client inboxes.

Failing to meet DMARC policy requirements, which is the foundational step for BIMI.

Using an unverified logo or incorrect SVG format, leading to display failures.

Not considering that spam folder placement will likely prevent BIMI logo display.

Expert tips

Focus on robust email authentication first. BIMI builds on a strong DMARC foundation.

Decouple the understanding of Email Service Provider (ESP) support from Email Client (MUA) support for BIMI.

Regularly check official BIMI Group resources for updated support lists and technical guidelines.

Remember that content quality and sender reputation still heavily influence inbox placement, even with BIMI.

Expert view

Expert from Email Geeks says: Cloudmark stamps headers that Mail User Agents (MUAs) like Apple Mail can then read and display the logo. It is crucial to distinguish between Apple Mail as a client and iCloud as an email service provider.

2023-10-11 - Email Geeks

Marketer view

Marketer from Email Geeks says: Apple uses both Cloudmark and Proofpoint, and the division of labor between these systems regarding BIMI implementation can be unclear.

2023-10-11 - Email Geeks

Final thoughts on BIMI and Cloudmark

While Cloudmark plays a significant role in authenticating emails for many mailbox providers, its support for BIMI primarily lies in validating the BIMI record and stamping the necessary headers. The ultimate display of your brand logo depends on the Mail User Agent (the email client) used by the recipient.

Major providers like Gmail, Yahoo Mail, and Apple Mail are strong proponents of BIMI, with varying requirements such as the need for a Verified Mark Certificate. If your recipients use these platforms, implementing BIMI is highly recommended for enhanced brand recognition and trust. For other providers, it's essential to research their specific MUA support, as Cloudmark's backend validation does not automatically ensure frontend display.

Prioritizing a robust DMARC implementation is the foundational step for BIMI, as it ensures your emails are authenticated and less likely to be blocked or sent to spam. By understanding the layered nature of BIMI support, you can strategically implement this standard to maximize its benefits across the broadest possible audience.