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Verified Mark Certificate (VMC) Explained
A Verified Mark Certificate (VMC) is a digital certificate issued by a certificate authority that proves a company owns a registered trademark. It is a mandatory requirement for the Brand Indicators for Message Identification (BIMI) standard to display a brand logo in a recipient's inbox.
Definition and Purpose
A VMC is a specialized SSL/TLS certificate that validates the legal ownership of a trademark. Unlike standard certificates that validate domain ownership, a VMC confirms that the organization sending the email has the legal right to use the logo associated with that trademark. This prevents unauthorized parties from spoofing a brand's visual identity in the inbox.
Mechanical Operation
The VMC works as part of the BIMI ecosystem. A sender publishes a BIMI DNS record containing a pointer to a SVG logo file and the VMC. When a receiving mail server sees the BIMI record, it checks the VMC to ensure the logo is authenticated. If the VMC is valid and the email passes DMARC checks with a reject or quarantine policy, the mail client renders the logo.
Importance for Senders
VMCs increase brand visibility and trust. By displaying a verified logo, senders can distinguish their official communications from phishing attempts. This visual cue helps improve open rates and provides a professional appearance. To implement this, senders can use SendHQ or its free tools (https://sendhq.cc/tools) to ensure their underlying DNS records are correctly configured.
Operational Requirements
To obtain a VMC, a company must first have a registered trademark with a government agency. The certificate authority then verifies this registration. Additionally, the sender must have a DMARC policy of p=quarantine or p=reject. Without a strict DMARC enforcement policy, the VMC will be ignored by receiving mail servers regardless of its validity.
Implementation Example
A company registers their logo as a trademark. They obtain a VMC from a qualified provider. They then add a TXT record to their DNS: default._bimi.example.com IN TXT "v=BIMI1; l=https://example.com/logo.svg; a=1". The receiving server validates the SVG file against the VMC and displays the logo in the user's inbox.
Questions teams ask
Is a VMC the same as an SSL certificate?
No. While it uses similar technology, a VMC specifically validates trademark ownership for BIMI, whereas an SSL certificate validates domain ownership for HTTPS.
Do I need a VMC for BIMI?
Yes, for most major email providers to display your logo, a VMC is required to prove the logo is a legally registered trademark.
Can I use a VMC without DMARC?
No. BIMI and VMCs require a DMARC policy of either quarantine or reject to be functional.