CG 20 10 vs CG 20 37: Why Reading Endorsement Form Numbers Is the Single Biggest Gap in COI Compliance

Ask a property manager whether their vendors carry additional-insured coverage and you'll almost always hear "yes — we require it." Ask whether those vendors carry completed-operations additional-insured coverage, and the answer usually becomes "we require it." Pull twenty of their COIs and read the ACORD 25 endorsement box, and you'll find that somewhere between 30% and 60% of them are only listing CG 20 10 — an ongoing-operations-only form that quietly leaves the manager uncovered for the exact claims most likely to arrive: the ones that surface months or years after the work is done.

This is not a paperwork quirk. It is the single biggest silent gap in vendor insurance compliance, and it is invisible to every COI system that only checks "is there an additional insured? yes/no."

This guide explains every ISO endorsement form a property manager should be scoring against, why generic yes/no tracking fails, and what changes when your compliance system actually reads the form numbers.

The Core Problem: "Additional Insured" Is Not a Single Thing

The certificate of insurance doesn't grant coverage. The underlying policy endorsement does. And there are several different endorsements — each with different scope — that the vendor's broker can attach to the policy when they issue you a COI.

From the certificate holder's perspective, all of them look the same in the ACORD 25 "Description of Operations" box: a line that might say "Property manager listed as additional insured per attached endorsement" or simply "Additional insured."

But beneath that language sit forms with radically different protection:

• CG 20 10 grants AI status for ongoing operations only.
• CG 20 37 grants AI status for completed operations only.
• CG 20 33 and CG 20 38 are blanket additional-insured forms covering both when properly drafted.
• CG 20 26 is a scheduled additional-insured form — AI status for the party explicitly listed, no blanket.

A vendor who carries only CG 20 10 is fully covered while they are on your property swinging a hammer. The day they roll up their drop cloths and leave, your AI coverage disappears. Eighteen months later when a ceiling collapses because an anchor was installed wrong, you're a third-party claimant against the vendor's policy with no contractual right to a defense.

Why Generic COI Tracking Misses This

Most COI tracking tools — spreadsheets, legacy platforms, and even the large enterprise systems — score the additional insured field with a single yes/no toggle. If the ACORD 25 form contains any reference to AI status, the box turns green.

That logic is structurally unable to distinguish CG 20 10 from CG 20 37. Both forms satisfy "is there an additional insured? yes." Only by reading the actual ISO form number can a system tell you whether completed-ops is present.

COIPulse reads the form numbers directly. When a COI arrives, the AI extraction identifies every endorsement form referenced in the ACORD 25 Description of Operations and on the attached endorsement pages. It categorizes each form by what it actually grants:

• CG 20 10 → ongoing operations AI
• CG 20 37 → completed operations AI
• CG 20 33 / CG 20 38 → blanket AI (ongoing + completed)
• CG 20 26 → scheduled AI

Your per-trade compliance rule then scores each category independently. A general contractor with only CG 20 10 will show as deficient on completed-ops AI while still passing on ongoing-ops, and the vendor's reason list will cite the specific form number — not a vague "additional insured missing" message that leaves your broker guessing.

The Full Form Ecosystem Worth Scoring

Additional insured is where most compliance gaps live, but the same form-number-level precision matters across five categories property managers commonly require:

1. Additional Insured (CG 20 10, CG 20 37, CG 20 33, CG 20 38, CG 20 26)

Covered above. The key principle: require both ongoing and completed operations, and accept either a true blanket form (CG 20 33/38) or a matched pair (CG 20 10 + CG 20 37). Never accept CG 20 10 alone for construction-related trades.

2. Waiver of Subrogation — General Liability (CG 24 04)

Waiver of subrogation on the general liability policy prevents the vendor's carrier from suing your organization for reimbursement after paying a claim involving your operations. The ISO form is CG 24 04.

Some policies include waiver on a blanket basis — if the insured agreed in a written contract, the waiver applies. Others require a scheduled waiver with your name on the endorsement. Either can be acceptable; what matters is that the form is present.

3. Waiver of Subrogation — Workers' Compensation (WC 00 03 13)

The WC waiver is the workers' compensation counterpart to CG 24 04. State-issued form in most jurisdictions, but the most common ISO form is WC 00 03 13. Without it, the vendor's workers' comp carrier can pursue your organization after paying out a claim to their employee injured on your property.

4. Primary and Non-Contributory (CG 20 01)

Primary and non-contributory status means the vendor's policy pays first, and your own policy doesn't contribute until the vendor's limits are exhausted. Without it, your carrier and the vendor's carrier can end up in a contribution fight after a claim, sometimes leaving you with higher premiums because your policy contributed to a loss it shouldn't have.

The relevant form is CG 20 01 or equivalent manuscript language in the general liability policy.

5. Per-Project / Per-Location Aggregate (CG 25 03, CG 25 04)

Most commercial general liability policies have a shared general aggregate that applies across all of the insured's operations. A vendor doing work for ten clients can exhaust the general aggregate on someone else's loss, leaving nothing for you.

Per-project aggregate (CG 25 03) or per-location aggregate (CG 25 04) gives your project or location its own dedicated aggregate limit — your claims don't compete with claims from the vendor's other clients.

What Form-Level Scoring Looks Like in Practice

Here is a realistic compliance rule for a general contractor doing construction work at a managed property:

| Requirement | Required Form(s) | |---|---| | AI — ongoing ops | CG 20 10 or CG 20 33 or CG 20 38 | | AI — completed ops | CG 20 37 or CG 20 33 or CG 20 38 | | Waiver GL | CG 24 04 | | Waiver WC | WC 00 03 13 | | Primary & non-contributory | CG 20 01 | | Per-project aggregate | CG 25 03 or CG 25 04 |

When a COI lands, COIPulse extracts every form number referenced, evaluates each requirement independently, and produces a reason list that looks like:

• AI ongoing ops: ok (CG 20 10 present)
• AI completed ops: missing (no CG 20 37 / 33 / 38)
• Waiver GL: ok (CG 24 04 present)
• Waiver WC: missing (WC 00 03 13 not cited)
• Primary & non-contributory: ok
• Per-project aggregate: missing (CG 25 03 / 04 not cited)

This is what a compliant COI actually needs to demonstrate — and it is what your broker, attorney, or auditor will look for the moment a claim appears.

Why This Matters More Than Any Other Compliance Check

Policy limits get most of the attention in COI compliance. "We require $1M GL." "We require $5M umbrella." Those checks are easy, which is why every tracking tool does them — and why, in practice, they are rarely where gaps exist. Vendors almost always have the limits on paper.

Form-level coverage is different. Brokers default to whatever endorsement they've used for the vendor's other clients, and that's almost always CG 20 10 alone. Completed-operations coverage is treated as an upgrade, quietly omitted unless the certificate holder specifically demands it.

Across a portfolio of 200 vendors, if even 40% are missing CG 20 37, your exposure to completed-ops claims compounds with every project that closes out. The issue doesn't surface until a slip, fall, leak, or collapse happens years later — and by then the vendor may have changed carriers, gone out of business, or let the policy lapse.

That is why form-level scoring — not yes/no AI tracking — is the compliance check that actually correlates with reduced litigation exposure.

Start Scoring Your Endorsements

COIPulse is the only COI compliance platform that reads ISO endorsement form numbers directly from the certificate and scores each category (AI ongoing, AI completed, waiver GL, waiver WC, primary & non-contributory, per-project aggregate) independently. You configure which forms are required per trade — a landscaper doesn't need per-project aggregate, but a general contractor probably does — and the system flags vendors missing specific forms with the form number cited in the reason.

Start free with 15 vendors and see exactly which of your existing COIs are quietly missing CG 20 37.