Beyond additional insured status, commercial subcontracts frequently require primary and noncontributory (PNC) language and waiver of subrogation (WOS) on the subcontractor's liability policies.
These appear on COIs as checkboxes or description text. Like additional insured, they only matter when the underlying endorsements are on the policy.
Primary and noncontributory
Primary means the sub's policy responds first to a covered claim — before yours.
Noncontributory means the sub's carrier should not seek contribution from your policy for covered amounts, subject to policy terms.
Together, PNC protects your GL program from becoming the first payer for claims arising from sub operations.
What to verify
- Contract specifies PNC on GL (and sometimes auto)
- Endorsement on policy — commonly CG 20 01 or equivalent state form
- COI description references PNC but endorsement must exist
- Applies to the correct parties (GC, owner as named in contract)
Waiver of subrogation
Subrogation is the insurer's right to pursue a third party after paying a claim. A waiver of subrogation means the carrier gives up that right — typically so they cannot sue you to recover losses they paid on the sub's policy.
In COI reviews, people often shorthand this as WOS insurance. The shorthand is common, but the requirement is not a separate policy. It is waiver wording added to the relevant insurance policy by endorsement.
Why contracts require WOS
If a sub's employee is injured due to a site condition you managed, their WC carrier might subrogate against your GL without a waiver. WOS blocks that recovery path when properly endorsed.
Critical timing rule
WOS must be in place before a loss occurs. Requesting waiver after an incident is too late.
What to verify
- WOS on GL, WC, and auto as contract specifies (not just GL)
- Endorsement form attached — CG 24 04 is common on GL
- Blanket WOS vs scheduled waivers match contract language
How these appear on ACORD 25
The certificate may show:
- Checkboxes for "Subrogation Waived" on policy lines
- Description box text referencing PNC and WOS
- Certificate holder listed with AI language
None of that substitutes for endorsements. Adjusters review policy endorsements, not certificate summaries.
Stacked requirements example
A typical commercial subcontract insurance clause requires:
- CGL $1M/$2M with AI (CG 20 10 + CG 20 37)
- Primary and noncontributory
- Waiver of subrogation on GL, WC, auto
- Umbrella following form
- 30-day cancellation notice to GC
Your compliance review must confirm each item — not approve the COI because limits look right.
Remodel GC note
Residential owner contracts are sometimes lighter on PNC/WOS than commercial work — but design-build remodels, condo rules, and high-value homes increasingly import commercial insurance schedules.
Read the owner contract before you flow requirements down to subs.
Review workflow
- Extract PNC/WOS requirements from subcontract template
- On each COI, check description + policy line checkboxes
- Collect endorsement PDFs or agent confirmation
- Store with COI in sub compliance record
- Re-verify at policy renewal — endorsements may not auto-renew
CoiLoop lets GCs add checklist items for PNC and WOS alongside AI verification so reviewers see contract context while reading the certificate.