Additional Insured Endorsements: The Complete Broker's Guide

Additional insured endorsements are the most commonly requested contractual insurance requirement — and the most common source of certificate compliance failures. Understanding the nuances of these endorsements is essential for every commercial lines broker.

Understanding Additional Insured Status

An additional insured is a person or organization added to a liability policy who receives coverage for liability arising out of the named insured's operations. The key word is "arising out of" — the additional insured's coverage is derivative of and connected to the named insured's work.

Additional insured status does not make someone a named insured. The coverage is narrower, and the additional insured typically has no right to receive policy notices or make policy changes.

The ISO Endorsement Landscape

ISO publishes multiple additional insured endorsement forms, each with different coverage scopes:

CG 20 10 — The workhorse endorsement for ongoing operations. The 04 13 edition provides coverage for liability arising out of the named insured's ongoing operations performed for the additional insured.

CG 20 37 — The completed operations companion to CG 20 10. This endorsement extends additional insured coverage to the products-completed operations hazard after the named insured's work is done.

CG 20 33 — A blanket additional insured endorsement that automatically grants AI status to any party the named insured is contractually required to add.

The edition date matters enormously. The 2004 revisions to CG 20 10 narrowed coverage significantly compared to earlier editions, requiring the additional insured to also obtain CG 20 37 for completed operations protection.

Contractual Requirements

Most commercial contracts specify additional insured requirements in their insurance provisions. Common language includes requests for "additional insured status on a primary and noncontributory basis" for "ongoing and completed operations." Brokers must parse these requirements carefully to ensure the right combination of endorsements is placed.

Verification Process

Verifying additional insured compliance requires checking that the endorsement exists on the policy, the edition matches or exceeds the contractual requirement, the additional insured is properly identified, and the coverage scope matches the contract.

Automated verification catches the subtle issues that manual review misses — like an older edition endorsement that technically satisfies the certificate but doesn't meet the contract's specific requirements.