The GC wants a cert before Monday. What that paper actually proves.

That paper did one job. It got you on site.

Read what the form says about itself

The standard form is the ACORD 25. Its own header: "THIS CERTIFICATE IS ISSUED AS A MATTER OF INFORMATION ONLY AND CONFERS NO RIGHTS UPON THE CERTIFICATE HOLDER. THIS CERTIFICATE DOES NOT AFFIRMATIVELY OR NEGATIVELY AMEND, EXTEND OR ALTER THE COVERAGE AFFORDED BY THE POLICIES BELOW." California Insurance Code 384 makes its own version mandatory: a certificate used as evidence of insurance in place of the policy has to say, in words to that effect, that it "is not an insurance policy and does not amend, extend or alter the coverage afforded by the policies listed herein."

A cert reports what the issuing agency put on it that day: carrier, policy number, dates, limits. The cancellation box says only that if a policy is canceled, "NOTICE WILL BE DELIVERED IN ACCORDANCE WITH THE POLICY PROVISIONS." Holding a cert doesn’t buy anybody a phone call.

Typing his name in the box is not the endorsement

The ACORD’s second boxed warning: "IMPORTANT: If the certificate holder is an ADDITIONAL INSURED, the policy(ies) must have ADDITIONAL INSURED provisions or be endorsed. ... A statement on this certificate does not confer rights to the certificate holder in lieu of such endorsement(s)."

The endorsement does the work. The cert describes one that either exists or doesn’t.

Which endorsement, and when it shuts off

ISO’s scheduled ongoing-operations form, CG 20 10 04 13, adds the scheduled party "but only with respect to liability ... caused, in whole or in part, by ... your acts or omissions ... in the performance of your ongoing operations." The same form carries an exclusion that shuts that status off for injury or damage happening after either of two points. One is all work at the location to be performed by or for the additional insured being finished. The other is the part of your work the claim arises out of being put to its intended use by anyone other than another contractor or subcontractor on the same project.

For roofing, that timing is the issue. The callback comes after the first real rain. Completed operations sits on a separate form, CG 20 37 04 13. Which forms are on your policy depends on what your carrier issued. Ask your broker by form number.

Two ceilings the cert doesn’t show

From the ACORD body: "LIMITS SHOWN MAY HAVE BEEN REDUCED BY PAID CLAIMS." A cert issued in March shows March.

Both forms add a second cap: where the coverage is required by contract, it "will not be broader than that which you are required by the contract or agreement to provide," and the endorsement "shall not increase the applicable Limits of Insurance shown in the Declarations." A contract demanding $5 million doesn’t create $5 million.

California trims these demands from the other end. Insurance Code 11580.04 says an additional insured endorsement issued in connection with a construction contract governed by Civil Code 2782(b) "shall not provide any duty of indemnity coverage for the active negligence of the additional insured."

The cert that costs you money is the one you collect

Part Five of the standard workers' comp policy sets your premium basis as payroll for your own people plus "all other persons engaged in work that could make us liable under Part One." Without payroll records for those people, "the contract price for their services and materials may be used as the premium basis," and that "will not apply if you give us proof that the employers of these persons lawfully secured their workers compensation obligations."

With a C-39 that gets tested every year. Insurance Code 11665 requires your carrier to run an annual payroll audit with an in-person visit to your place of business to verify your employee count, and WCIRB rules require a physical audit of the complete policy period on every C-39 policy, whatever the premium.

The policy says "proof." It doesn’t define what that means. Get the answer from your carrier before the auditor is in your office.

A sub’s cert says nothing about his license

Under BPC 7125.2, failure to maintain workers' comp coverage "shall result in the automatic suspension of the license by operation of law," backdated to the lapse. CSLB says work done while a license is suspended "is considered to be unlicensed." BPC 7031(b) lets someone who used an unlicensed contractor’s services sue "to recover all compensation paid," and BPC 7118 makes hiring one a cause for discipline against your license.

A certificate issued in January proves nothing about license status today.

Do this on your next slow morning

Pull up the last cert your office sent out and check the policy dates against when that job will actually be finished, not when it starts. Then send your broker one email: ask for copies of the additional insured endorsements on your GL by form number, and whether any of them reach past the day you’re off the roof. Ask for the endorsements, not another cert.

Run it in reverse on the two or three subs you use most. Certificate from their broker directly, plus their CSLB license status.

Aster keeps a requirements checker at https://roofercomp.com covering what C-39 and the other CSLB classes are required to carry, if you’d rather check yours before a GC asks.

Aster National Insurance Group, Duarte CA. CA Lic #0N10039. General information only, not legal advice and not a coverage determination. Any coverage depends on the terms of the policy issued. Statutes cited are current as of August 2026; check the current text at leginfo.legislature.ca.gov and cslb.ca.gov.