Construction teams talk about "getting the COI" as if it closes the compliance loop. It does not.
A Certificate of Insurance is a summary. An endorsement is a legal change to the insurance policy. When those two documents disagree, the endorsement wins — and your certificate holder status does not help you.
What a COI does
The ACORD 25 certificate:
- Lists policies, limits, and dates at issuance
- Names the certificate holder
- May describe endorsements in a text box
- Is explicitly not a policy and does not amend coverage
Carriers and state regulators treat COIs as informational only.
What an endorsement does
An endorsement modifies the underlying policy:
- Adds additional insured parties
- Grants waiver of subrogation
- Changes primary/noncontributory status
- Extends completed operations coverage
- Schedules specific project parties
Without the endorsement on the policy, a COI line that says "additional insured" is marketing — not coverage.
The gap that creates claims exposure
Typical failure sequence:
- Subcontract requires AI + WOS + PNC
- Sub sends COI with description box listing all three
- GC files COI, sub starts work
- Claim occurs — carrier denies AI defense because endorsement was never issued
- GC's own GL responds; retention and indemnity disputes follow
This is not rare. It is the default outcome when teams equate certificate collection with compliance.
COI vs endorsement: quick reference
| Question | COI | Endorsement |
|---|---|---|
| Proves policy existed? | Yes (on date issued) | Part of policy |
| Creates additional insured? | No | Yes, when AI form attached |
| Legally binding coverage change? | No | Yes |
| What claim adjusters review? | Sometimes for orientation | Always |
Endorsements GCs should know
- CG 20 10 — AI ongoing operations
- CG 20 37 — AI completed operations
- CG 24 04 — Waiver of subrogation (common GL form)
- CG 20 01 — Primary and noncontributory (when required)
Blanket endorsements may cover all parties required by written contract — but you still verify the blanket form is on the policy.
How to verify endorsements without slowing projects
- At onboarding: COI + endorsement PDFs (or agent confirmation letter)
- In review: Match form numbers to subcontract language
- In storage: Keep endorsements attached to the sub record, not orphaned in email
- At renewal: Re-collect endorsements when policies renew — AI does not automatically roll forward on all forms
Remodel GC angle
On renovation projects, owners and designers care about completed operations exposure long after subs leave. A COI that only proves day-one coverage does not satisfy a lender's closeout package if CG 20 37 was never endorsed.
Document the full chain: COI + endorsements + renewal history.
Software vs spreadsheets
Spreadsheets track expiration dates — barely. They do not surface "AI mentioned on COI but endorsement missing" because that requires structured review against requirements.
CoiLoop's review flow shows the uploaded COI beside your configured checklist (AI, WOS, limits) so gaps are visible before you approve the sub.
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