Causes of Loss Forms — insurance Services Office, Inc. (ISO), commercial property insurance forms that establish and define the causes of loss (or perils) for which coverage is provided. A causes of loss form is combined with one or more coverage forms, the commercial property conditions form, the common policy conditions form, and the declarations to make up an ISO commercial property policy. There are three causes of loss forms: the basic, broad, and special causes of loss forms. The basic and broad causes of loss forms are named perils forms; they provide coverage for loss from only the particular causes that are listed in the policy as covered. The special causes of loss form is an all risks form; it provides coverage for loss from any cause except those that are specifically excluded.