What Is an Additional Insured Endorsement (and Why Does It Matter)?
You require a vendor to insure you. They send a certificate of insurance, your company name is printed on it, and the box gets checked. But there's a quiet trap on that document: the spot where your name appears determines whether your vendor's policy actually protects you — or whether you just received a piece of paper that proves nothing about your own coverage.
The difference comes down to two phrases that look similar and mean opposite things: certificate holder and additional insured. Confusing them is one of the most common — and most expensive — mistakes in vendor risk management.
What does "additional insured" actually mean?
An additional insured is a third party who is added to someone else's insurance policy so that the policy's coverage extends to protect them too.
When your vendor names you as an additional insured on their general liability policy, their insurer agrees to defend and indemnify you for claims arising out of that vendor's work. If their crew damages property or injures someone on your site, your defense costs and liability can be picked up by their carrier — not yours. That's the entire point of requiring insurance from vendors in the first place: you want their coverage to absorb the risk their work creates.
This extension isn't automatic. It's granted through an additional insured endorsement — a specific form attached to the policy that names you (or a class of parties you belong to) and spells out the scope of the protection. Standard industry forms exist for exactly this purpose, but the key idea is simpler than the form numbers: the endorsement is what amends the policy itself. Without it, the policy covers only the named insured — your vendor — and nobody else.
Why isn't being a certificate holder enough?
Because the certificate holder is just the person being notified.
A certificate of insurance is an informational snapshot. The certificate holder is the party the document is addressed to — the one entitled to receive a copy and, often, advance notice if the policy is cancelled. That's it. Being listed as certificate holder gives you no coverage rights whatsoever. You are a recipient, not a beneficiary.
Here's the failure mode that catches people: a vendor's office staff fills out the certificate, types your company into the "Certificate Holder" box at the bottom, and sends it over. It looks complete. Your name is right there. But if you were never added as an additional insured by endorsement, the coverage never reached you. When a claim hits, the vendor's insurer looks at the policy, sees you aren't an insured party, and denies your tender. Now you're defending the claim with your own policy — or out of pocket.
The certificate showed your name. It just showed it in the wrong place. Current and "has my name on it" are not the same as covered.
How do I confirm I'm actually covered?
Verifying additional insured status takes more than glancing at the certificate. Work through these checks:
- Find the additional insured box, not the certificate holder box. On a standard COI (the ACORD form), there's a "Description of Operations" area and check-boxes indicating whether additional insured status applies. Your entity should be referenced there — not only in the certificate holder field at the bottom.
- Ask for the endorsement itself. The certificate is a summary; the endorsement is the binding document. Request a copy of the additional insured endorsement attached to the policy and confirm it names you or a defined class that includes you.
- Check the scope and wording. Some endorsements cover only ongoing operations and exclude completed work; some are limited to liability "caused by" the vendor. Match the language to what your contract requires.
- Confirm it's primary and non-contributory if your contract calls for it — otherwise your own insurer may end up sharing the loss.
- Re-verify on renewal. An endorsement on last year's policy doesn't carry forward automatically. Each new policy term needs to be checked again.
Where Certify comes in
Certify is an AI agent that reads every certificate of insurance and the endorsements behind it, then checks them against your requirements — including whether your entity is actually named as an additional insured, not just listed as a certificate holder.
You forward or upload the COIs. Certify extracts the coverage, limits, expiry, and additional insured status, flags exactly where you're exposed, and drafts the follow-up email to the vendor so the gap gets fixed before a claim tests it. It's built for property managers, general contractors, and franchisors who can't afford to discover the difference between "named" and "covered" the hard way.
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Never get caught with an expired or wrong COI
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