After 17 years of overseeing the “Ask an Expert” service of the IIABA Virtual University, I learned that very few agents could tell the difference between ISO and non-ISO forms. When an agent submitted a question to the service, they were told that we needed the full ISO policy form number unless it was not an ISO form, in which case we needed a copy of the proprietary form. All too often, we’d be provided a policy form number the agent thought was an ISO form, but it clear wasn’t. So, how do you tell the difference?
To answer that question, I wrote an article about three basic tests that can usually be used to determine if a form is an unaltered ISO form or not:
Is It ISO or Is it Memorex Insurance Company?
One of the tests in the article is the form number structure. You can read about it by clicking the link above. But aside its value in distinguishing between ISO and non-ISO forms, the form number tells you something about the form before you even examine it.
For example, I wrote two articles about the importance of reviewing policy deliverables because carriers will sometimes attach exclusionary or limiting policy forms that the agent may be able to negotiate for removal or replacement by less onerous forms:
Be Careful What You DON’T Ask For
Be Careful What You DON’T Ask For (sequel)
How these three articles work together to make the primary point of this article is that you can often tell if an endorsement is “bad” simply by the form number. To illustrate, if you have an ISO CGL policy and one of the endorsements added by the insurer has a form number of the structure “CG 21 ## MM YY,” the “21” category of CGL endorsements tells you that this form excludes something because the “21” category is “Exclusion Endorsements.” This should be a red flag to the agent or insured that this form is problematic and an effort to have it removed or replaced is advisable if possible.
ISO maintains the following lines of insurance:
COMMERCIAL LINES
- Agricultural Capital Assets (Output Policy)
- Businessowners
- Capital Assets (Output Policy)
- Commercial Auto
- Commercial Inland Marine
- Commercial Property
- Commercial Umbrella
- Crime And Fidelity
- E-Commerce
- Employment-Related Practices
- Equipment Breakdown
- Farm
- Financial Institutions
- General Liability
- Management Protection
- Market Segments (All Programs)
- Medical Professional Liability
- Professional Liability (Other Than Medical) – Insurance Agents And Brokers Professional Liability
- Professional Liability (Other Than Medical) – Lawyers Professional Liability
- Professional Liability (Other Than Medical) – Real Estate Agents And Brokers Professional Liability
PERSONAL LINES
- Dwelling Property
- Homeowners
- Motorcycle
- Personal Auto
- Personal Liability
- Watercraft
Below is a listing of the four major ISO commercial lines of insurance and what the category numbers mean.
BUSINESSOWNERS
AP Applications
DS Declarations and Scheduled
IN Index
00 Coverage Forms
01 Amendatory Endorsements
02 Cancellation and Suspension Endorsements
03 Deductible Endorsements
04 Additional Coverages
05 Additional Coverages
06 Additional Coverages
07 Special Trade Contractors Endorsements
08 Professional and Errors and Omissions Liability Endorsements
10 Causes of Loss
12 General Endorsements
14 Additional Coverages
16 Additional Coverages
17 Condominium Coverage
COMMERCIAL AUTO
AP Applications
DS Declarations and Scheduled
00 Coverage Forms
01 Amendatory Endorsements
02 Cancellation and Suspension
03 Deductible Endorsements
04 Additional Coverages for Commercial Auto
05 Amendatory Endorsements
20 Special Types of Endorsements
21 Uninsured Motorists Endorsements
22 No-Fault Endorsements
23 Commercial Automobile Endorsements
24 Public Transportation Endorsements
25 Garage Endorsements
26 Single Interest Endorsements
31 Uninsured Motorists Endorsements
60 Reserved for future use
99 Common Coverages and Rating Procedures Endorsements
COMMERCIAL PROPERTY
AP Applications
DS Declarations and Schedules
00 Coverage Forms
01 Amendatory Endorsements
02 Cancellation and Suspension Endorsements
03 Deductible Endorsements
04 Additional Coverages
10 Causes of Loss
11 Builders Risk Endorsements
12 General Endorsements
13 Value Reporting Form and Related Endorsements
14 Additional Covered Property / Property Not Covered
15 Time Element Endorsements
16 Applications, Worksheets and Rating Identification
17 Standard property Policy Condominium Endorsements
19 Supplemental Schedules
60 Leasehold Interest Factor Tables
99 Miscellaneous Endorsements
GENERAL LIABILITY
AP Applications
DS Declarations and Schedules
00 Coverage Forms
01 Amendatory Endorsements
02 Termination and Suspension Endorsements
03 Deductible Endorsements
04 Additional Coverage Endorsements
20 Additional Insured Endorsements
21 Exclusion Endorsements
22 Special Provisions For Certain Types of Risks Endorsements
23 Risk Specific Endorsements
24 Coverage Amendment Endorsements
25 Amendment of Limits Endorsements
26 Amendatory Endorsements
27 Claims-Made Only Endorsements
28 Miscellaneous Coverage Parts Endorsements
29 Miscellaneous Coverage Parts Endorsements
30 Underground Storage Tank Endorsements
31 Miscellaneous Coverage Parts Endorsements
32 State Specific Endorsements
33 Miscellaneous Coverage Parts Endorsements
99 Miscellaneous Endorsements
For a more exhaustive listing of lines of insurance, contact your carriers.
Bill Wilson
Latest posts by Bill Wilson (see all)
- The Invisible But Potentially Catastrophic Homeowners Exclusion That’s Not An Exclusion - September 19, 2023
- Revisiting the Illusory Coverage Assertion Following a Claim Denial - September 19, 2023
- FREE Webcast: How to Survive and Thrive in a Hard Market - August 1, 2023
