Short answer
Older additional insured endorsements covered injury “arising out of” your work, and courts read that wording broadly. Newer endorsements cover injury caused in whole or in part by your acts or omissions. In Burlington v. NYC Transit (2017), New York’s highest court held that this wording requires your conduct to be a proximate cause of the injury. In practice, additional insured status protects the owner mainly for your share of fault. Whether a policy responds depends on its wording and the facts.
What additional insured status is
Additional insured status extends part of your general liability (GL) policy to another party, such as an owner, neighbor or property manager. That party can then make a claim under your policy for certain losses. The coverage is limited by the endorsement, and it shares your policy limits.
Many design firms confuse this with a certificate holder, who only receives proof of coverage. Professional liability policies also work differently from GL policies and usually do not offer additional insured status in the same way.
Arising out of vs. caused in whole or in part
“Arising out of” is broad wording. Courts often read it to mean the loss had some connection to your work, even a loose one. An owner could qualify as an additional insured without any fault on your part.
Caused in whole or in part is narrower. The injury must be caused, at least partly, by your acts or omissions. A loss that only happened near your work, or that you had no part in causing, falls outside that language.
Many ISO-based endorsements adopted the caused in whole or in part wording. Indemnity clauses in contracts often use similar phrasing. Wording still varies by carrier and form, so the actual endorsement controls.
What Burlington decided
In Burlington Ins. Co. v NYC Tr. Auth., the Court of Appeals reviewed an endorsement that covered injury caused, in whole or in part, by the named insured’s acts or omissions. The court held that this wording applies to injury proximately caused by the named insured. A “but for” connection was not enough.
The facts involved a worker injured on a construction project. The evidence showed the contractor who bought the policy was not at fault. The court held that the owner’s coverage as additional insured did not apply on those facts.
You can read the full opinion in the official New York Courts reporter.
Commentators note that the decision addressed the duty to indemnify and did not decide an insurer’s duty to defend. Later cases have worked through that distinction. Anyone applying the case to a specific loss should work with qualified counsel.
Why owners still ask for it
Owners ask for additional insured status because it is one layer of risk transfer. It sits next to indemnity clauses, waivers and primary and non-contributory wording. Most of that protection comes from the contractors’ policies, since contractors control the work.
The same checklist often lands on architects and engineers. If you want to see why, our article on Labor Law 240 for design firms explains where New York owners get their exposure.
An owner may treat your endorsement as broad protection. In reality, the caused in whole or in part wording ties that protection to your own involvement in the loss. Explaining this calmly can help when a neighbor or owner pushes for more.
What to check on your policy
Start with the endorsement itself, not the certificate. Ask your agent for a copy of the actual form. Then work through these points:
- Whether your policy includes blanket additional insured status when a written contract requires it
- The exact wording, such as arising out of or caused in whole or in part
- Whether the endorsement applies on a primary and non-contributory basis when the contract requires it
- Whether completed operations additional insured coverage is included
- Whether the contract asks for broader wording than your policy provides
If the contract asks for more than the policy offers, raise it early. Some firms can add an endorsement. Others negotiate the contract language instead.
What we see at Hardcover
A New York neighbor asked one of our engineering clients for broad additional insured coverage. We explained that the endorsement on the engineer’s GL responds to injury caused by the engineer’s own operations.
That explanation changed the conversation. The neighbor had assumed the endorsement worked like a separate policy for their benefit. Once the wording was on the table, both sides could discuss what the request actually needed.
Related questions
If they are additional insured, are they covered for anything that happens on the job?
Usually not. Coverage generally depends on the endorsement wording and on whether the loss connects to your work. Under caused in whole or in part wording in New York, courts look for your conduct to be a proximate cause.
What does “caused in whole or in part” mean on an additional insured endorsement?
In New York, courts have read it to require that the named insured’s conduct be a proximate cause of the injury. A loose connection to your work is generally not enough under that wording.
Is additional insured status the same as being fully covered?
No. It is usually limited to losses connected to the named insured’s work and fault, depending on the wording. The owner’s own negligence is typically a separate issue.
General education, not legal advice. Hardcover is an insurance agency, not a law firm.